As always, thanks for the prompt replies and great advice guys; it makes all the difference, especially for persons like myself that aren't developers by trade/practice/experience.
I added a line to .htaccess to allow access to this php file - for the life of me I can't figure out why everything was working before (with 2-factor On + .htaccess = both of these existed before ever even installing the login module) and then suddenly not, but that is certainly all on my end/not of issue with the module itself.
I owe you guys a positive rating on joomla extensions page(s) and fwiw I also have upcoming blog posts on using the entire JFBC suite - excellent product(s) and even better support - much appreciated!