It rings true to me that big corporations tend to be not racist. That doesn’t mean, however, that no one or no group of people working for Microsoft (or any other corporation for that matter) will ever be racist. And if they are doing PR or the ads it is very much possible that their racism becomes visible as something that “Microsoft” is or does.
I don’t, however, think that this is the case here. But it was stupid to doctor with the picture. It’s a generic enough photo, so why not just buy a new one for the Polish ad?