@FamiComplex Did you contact your employer about this? Maybe they can shed some light on how it was donated so you or they know who to contact?
Worst case: you will have to wait till february. By then Stadia is open for all. Am I correct?
True @Morn, but if he/she won a premiere or founders edition, then it comes with 3 months Stadia Pro also for free, so an invitation code would then be good.
Was that the case for you? I mean normally you can get the invitation code from Stadias customer support, but you need Indeed a serial number (on your hardware) and the order-number (from the buyer). I can understand it might be a bit difficult if this was won in an auction, but I don't see really a way than to contact the customer support again and try to explain the situation or contact the person who held the auction, because they must have more information. Maybe @GraceFromGoogle can also escalate this further for you, especially because you mentioned it was donated by Google, but no guarantee on this.
@FamiComplex I'm not sure who your employer is, so I can't say this for a fact... but it's highly unlikely that Google directly donated the system to your company's auction. Someone at your company probably purchased it to go toward the auction, or at minimum would have had to have ongoing contact with someone at Google to facilitate a donation.
I would speak to the employer again and find out who the Charity Auction organizer was, and then start from there to find out who arranged the donated Stadia. Whoever arranged it is likely the person who has the code. If they truly never did get a code, then they should be able to contact whomever they worked with at Google to arrange the donation and get one.
But I think your search has to start with the Charity Auction organizer.
There is no hardware, only peripheral's a chromecast ultra and a game controller, both not technically required to use Stadia, just allows use of a TV and a controller to play ... find someone to give you a buddy pass, otherwise you have to wait until public launch...