Did you get this resolved?I just got a letter from the IRS disputing my $7,500 tax credit for a 2019 Bolt EV purchased 3/3/19. It said the VIN is invalid (it's not). And it said I need to send in a copy of the bill of sale and the manufacturer's certification.
Instructions for 2019 Form 8936 point to this web page that lists credit elegibility and amount by manufacturer, model and date put into service. I'm going to send them a printout of the General Motors, LLC section on that IRS web page.
Web searches indicate that requesting a certification from manufacturers or their dealers leads nowhere.
It looks like the IRS is serious about catching fraud through this tax credit.
Also, did you e-file or paper file? If paper filing, looks like one would have to mail in a copy of the purchase paperwork.