In essence one line is all you need (once you have set-up all the variables and such):

use Modern::Perl;
use Data::Dumper;

my $text= join '', <DATA>;

my %customers;

$customers{$_}++ for $text =~ m/{(.*?)}/g;

say Dumper(\%customers);

__DATA__
AB1\tA{Daniel Wright}\sA{Jack Smith}\sB{Jane Goodwin}
QW1\tA{Samantha Patton}\sC{Timothy Eeckles}
AR2\tA{Jane Goodwin}
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Output:

$VAR1 = {
          'Jane Goodwin' => 2,
          'Daniel Wright' => 1,
          'Timothy Eeckles' => 1,
          'Jack Smith' => 1,
          'Samantha Patton' => 1
        };
[download]