You're getting the Insecure $ENV{PATH} error because Perl thinks you're trying to execute a shell command from within the script. On first glance, you're not. But on a careful second glance, you're using backticks (`) where you mean to be using single quotes ('). See if you can spot where.

When Perl sees backticks in conjunction with -T, it requires that $ENV{PATH} be untainted, to prevent exploits whereby someone drops a command of the same name into some place in your PATH that you don't expect it to be.