0ld_is_g0ld - Perl questions

I bumped into this trying to work with the PDF and, without giving anything away, am pulling my hair out trying to figure out why a related Perl script isn’t working. I found another way to get past the step, but I wanted to get a clue why this part failed.

Is there anyone out there that can explain why a certain tool that I loaded onto linux itself (can run from command line, see man pages etc.) and can manually run a Perl script I made to test (that calls Image::{ToolName}) will not be found by the most obvious Perl script mentioned as needed for the beginning of this challenge?

Pdfcrack it.

I have no idea what you’re trying, but “john” will do this password cracking. The point is: find a good word list.
Because i have no idea about the list i should use, I’ve created a bash file to iterate thru some directories with word files and try them one by one.
I got my password…
At the moment trying to understand how to write the flag, since it is very easy to find out once you open the file.

I started by trying to use the john2pdf.pl script, but in the end it was easier to use a tool directly against the pdf as mentioned previously.