Fred,
I agree that it would be great to know more about the set even if it weren't from 1951. Although, it would obviously hurt the value if there were conclusive proof. As for what you've laid out so far, I think it is interesting but do not believe it really demonstrates anything about the actual age of the Wheaties product. There could just as easily be a mistake on the archive, etc., or it could not be a first edition photo (or whatever the photograph collectors call them)
To really figure things out, I think we would need an expert on uniforms to weigh in and determine if it is actual possible that these are 1951 uniforms for these players. I honestly just don't know enough about them myself to make a call.
And, Chris, not a chance
At least not yet.