UPDATE:
I once again reset my cache to see what would happen and I was able to recreate the error 500 which then became a 403. After a bit of investigation, it was determined there was an error with an .htaccess file. I have no clue as to why or how, but they corrected it and my site is back at 100%. I also got some advice on converting the database tables as well. Thank you for the direction!
Ford Doctor's post in Site Down After Database work and Clearing Cache was marked as the answer