# After this line from snippet 1...
my %testHash = ( \@multiKey1 => \@stuff1, \@multiKey2 => \@stuff2, \@multiKey3 => \@stuff3);

# ... add this:
use Data::Dumper;
print Dumper \%testHash;

# And run the snippet.

__END__
Output:

$VAR1 = {
          'ARRAY(0x98a9b4)' => [
                                 '6',
                                 '7'
                               ],
...
...