I don't know answer to your question, but you can try use perl 'sigtrap' module to get stacktrace, and possibly temporary replace try/catch/$_ with 'unless defined eval { }'/$@ , to debug your code.
UPD: For example 
 unless (defined eval { $self->_run($self, $row_id, $subject); 1 })
  { $logger->error("run($row_id): $@\n") };
  $self->_clear_subject;

[download]
this way you'll check if that is the problem with "my $_" or no.

In reply to Re: Try::Tiny catch block with $_ eq '' by vsespb
in thread Try::Tiny catch block with $_ eq '' by dd-b

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