Similar solution, but not with single regex:

#!/usr/bin/perl

use strict;
use warnings;

# https://perlmonks.org/?node_id=11148806

my $text = 'This is arbitrary just an arbitrary just example of text j
+ust arbitrary.';

@_ = qw( ju.. arb.{1,4}ary );

$text =~ m/
    (?:(?:This)|(?:That))
    .*? (??{ $_[ 0 ] })
    .*? (??{ $_[ 1 ] })
    /x and
    $text =~ s/
    (??{ "(*FAIL)" x ! @_ })
    .*? \K ( (??{ $_[ 0 ] }) ) (?{ shift @_ })
    /<<<$1>>>/gx;

print $text, "\n";
[download]

OUTPUT (excluding warnings):

This is arbitrary <<<just>>> an <<<arbitrary>>> just example of text j
+ust arbitrary.
[download]

P.S. capture group is redundant.