That would not surprise me at all -- I don't think it would even surprise Urahara at all. I mean, he does know what Mayuri is capable of, and he does know that Mayuri doesn't want to play second fiddle to his priorities, no matter how fun it may be to make innocent people dissolve. He has a daughter to build!

But selling him out for allegedly moral reasons would definitely be one way that the Soul Society would come to think, "Well, Kurotsuchi is a deviant, horrifying, disturbing, soulless shell of a man, but at least he's a step up from Urahara!"