Don't nest named subroutines. You'll just get problems.

Didn't you notice any "%s will not stay shared" warnings?
Didn't you notice any "subroutine %s redefined" warnings?
You've already noticed it isn't scoped as you expected.

I use

sub recursive {
   ...

   local *helper = sub {
      ...
      helper(...) if $cond;
      ...
   };

   ...
   helper(...);
   ...
}
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