...
        if ( $columns[6] != 0 ) {

            # skip exclusions
            if (ref (my $excl = $exclusions{$columns[1]} ) eq "ARRAY") {     # <---
                next if grep $_ == $columns[6], @$excl;                      # <---
            }
            
            $lastresult_of{ $columns[1] } = $columns[6];
        }
        ...