Excellent suggestion++. You forgot the capturing parentheses, though, so instead of wondering why the dispatch table and the subs are working together you'll be wondering why $1 isn't what you think it is. :-)

Change

my $re = join '\|', keys %dispatch;
if( $line =~ m/$re/ )
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to either

my $re = '(' . join( '|', keys %dispatch ) . ')';
if( $line =~ m/$re/ )
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or

my $re = join( '|', keys %dispatch );
if( $line =~ m/($re)/ )
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