Is the “shady” transmission builder a legit shop, or a guy doing it out of his garage? If so, who was it? Glad you got that shit straightened out.
I had a shop in MI. do my trans. The shop is named, “Certified.” The trans failed after a few thousand miles. Called, pulled it…ect got a call, informed me that it was a, “shit happens” kinda thing, ( valve body soft gasket blew out the trans has higher pressure than stock) So, got it back…awsome trans. …for FWD. 
A shop in NJ (maybe in NY now) named, “Dynotech”, do GREAT work. Always hear good things from them. The specialize in the 200R4, and now doing the 4T65E-HD trans (my fwd trans).
If I see you at the track this year, I'll say, "hi" this time.
Have fun.