I think this is a very broken extension. Are you sure its worth keeping it? Unless it works for someone else which I doubt.
1) I needed to change to
$file = company_path().'/pdf_files/'.$id.'.pdf';
$file = $comp_path.'/'.user_company(). '/pdf_files/'.$id.'.pdf';
to get it to kick start ..this is for my two different environments.
2) Inserting anything (garbage) in the test Sql box passes with flying green colors.
Something is genuinely wrong with this extension.
I am ready to spend time testing if you guide me to something that is useful..