Something like this?

#!/usr/bin/perl

# https://perlmonks.org/?node_id=1226425

use strict;
use warnings;

my %hash;
my ($header, @rules) = grep /\w/, <DATA>;
my (undef, @fieldnames) = $header =~ /\w+/g;

findnext(\%hash, 1, 'A', '00');
use Data::Dump 'dd'; dd \%hash;

sub findnext
  {
  my ($refh, $rule, $stage1, $stage2) = @_;
  for my $row (@rules)
    {
    if($row =~ /^\W+(\w+)\W+$rule\W+$stage1\W+$stage2\W+(\w+)\W+(\w+)\
+W+(\w+)/)
      {
      my ($return, $nextrule, $nextstage1, $nextstage2) = ($1, $2, $3,
+ $4);
      my %values;
      @values{@fieldnames} =
        ($rule, $stage1, $stage2, $nextrule, $nextstage1, $nextstage2)
+;
      $refh->{$return}{ROWDATA} = \%values;
      findnext($refh->{$return}, $nextrule, $nextstage1, $nextstage2);
      }
    }
  }

__DATA__
* return * rule * stage1 * stage2 * next_rule * next_stage1 * next_sta
+ge2 *
**********************************************************************
+*****
*   ret1 *    1 *     A  *     00 *         2 *           B *         
+ 10 *
*   ret2 *    1 *     A  *     00 *         5 *           D *         
+ 23 *
*   bob1 *    2 *     B  *     10 *         5 *           D *         
+ 23 *
*   bob2 *    2 *     B  *     10 *         6 *           E *         
+ 44 *
*   dog1 *    3 *     B  *     10 *         6 *           E *         
+ 44 *
*   dog2 *    4 *     C  *     10 *         6 *           E *         
+ 44 *
*   cat1 *    5 *     D  *     23 *         7 *           F *         
+ 55 *
*   cat2 *    5 *     D  *     23 *         7 *           F *         
+ 56 *
*   cat3 *    5 *     D  *     23 *         7 *           F *         
+ 57 *
*   hit1 *    6 *     E  *     44 *         7 *           G *         
+ 55 *
*   hit1 *    6 *     K  *     14 *         7 *           H *         
+ 55 *
*   hit2 *    6 *     E  *     44 *         7 *           G *         
+ 56 *
**********************************************************************
+*****
[download]

Outputs:

{
  ret1 => {
            bob1    => {
                         cat1    => {
                                      ROWDATA => {
                                        next_rule => 7,
                                        next_stage1 => "F",
                                        next_stage2 => 55,
                                        rule => 5,
                                        stage1 => "D",
                                        stage2 => 23,
                                      },
                                    },
                         cat2    => {
                                      ROWDATA => {
                                        next_rule => 7,
                                        next_stage1 => "F",
                                        next_stage2 => 56,
                                        rule => 5,
                                        stage1 => "D",
                                        stage2 => 23,
                                      },
                                    },
                         cat3    => {
                                      ROWDATA => {
                                        next_rule => 7,
                                        next_stage1 => "F",
                                        next_stage2 => 57,
                                        rule => 5,
                                        stage1 => "D",
                                        stage2 => 23,
                                      },
                                    },
                         ROWDATA => {
                                      next_rule => 5,
                                      next_stage1 => "D",
                                      next_stage2 => 23,
                                      rule => 2,
                                      stage1 => "B",
                                      stage2 => 10,
                                    },
                       },
            bob2    => {
                         hit1    => {
                                      ROWDATA => {
                                        next_rule => 7,
                                        next_stage1 => "G",
                                        next_stage2 => 55,
                                        rule => 6,
                                        stage1 => "E",
                                        stage2 => 44,
                                      },
                                    },
                         hit2    => {
                                      ROWDATA => {
                                        next_rule => 7,
                                        next_stage1 => "G",
                                        next_stage2 => 56,
                                        rule => 6,
                                        stage1 => "E",
                                        stage2 => 44,
                                      },
                                    },
                         ROWDATA => {
                                      next_rule => 6,
                                      next_stage1 => "E",
                                      next_stage2 => 44,
                                      rule => 2,
                                      stage1 => "B",
                                      stage2 => 10,
                                    },
                       },
            ROWDATA => {
                         next_rule => 2,
                         next_stage1 => "B",
                         next_stage2 => 10,
                         rule => 1,
                         stage1 => "A",
                         stage2 => "00",
                       },
          },
  ret2 => {
            cat1    => {
                         ROWDATA => {
                           next_rule => 7,
                           next_stage1 => "F",
                           next_stage2 => 55,
                           rule => 5,
                           stage1 => "D",
                           stage2 => 23,
                         },
                       },
            cat2    => {
                         ROWDATA => {
                           next_rule => 7,
                           next_stage1 => "F",
                           next_stage2 => 56,
                           rule => 5,
                           stage1 => "D",
                           stage2 => 23,
                         },
                       },
            cat3    => {
                         ROWDATA => {
                           next_rule => 7,
                           next_stage1 => "F",
                           next_stage2 => 57,
                           rule => 5,
                           stage1 => "D",
                           stage2 => 23,
                         },
                       },
            ROWDATA => {
                         next_rule => 5,
                         next_stage1 => "D",
                         next_stage2 => 23,
                         rule => 1,
                         stage1 => "A",
                         stage2 => "00",
                       },
          },
}
[download]

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