Wow what a nightmare!
I would stay on this for sure! Post it all the good and the bad. I hope GM handles this for you quickly. I had a service manager try to strong arm me over a warranty issue before and I'll never own another Toyota again due to that experience. Thinking about it still makes me mad.
Good luck and I hope someone steps up and helps you with these issues. I know from my business you can have 1000 rights and just 1 wrong but the 1000 rights shows your quality but how you handle that 1 wrong shows your character.