Crysis 3 was never ever planned. Crytek had tested their engine on the Wii U just for the sake of it, but they never had any plans to release it on the Wii U.
In June last year this was said:
"My opinion of the Wii U is very high," he told CVG. "It's just that we didn't have a business case unfortunately that justifies us making a game for it."
"It doesn't mean that CryEngine 3 doesn't run on Wii U - it actually runs beautifully," he added. "In fact, there actually is a game in development from a respected developer that we will be announcing. I've seen the game running and it looks really great."