KW has burned bridges and would never be considered for the BYU HC position at this point.
Sitake has been able to walk the tightrope of friend / enemy about as well as anyone that I can think of who has been an BYU alum / LDS / Utah coach in the last 30 years. The BYU door is open for him just as wide as the Utah door is, but I think his lack of HC experience actually is a bigger hindrance for a BYU HC position, than a Utah HC position, simply because his players would walk into Dr. Hills office and in Rudy style, put their uniforms on their desk and say, put Sitake in, but he has plenty of friends at BYU or that are in the BYU camp.
But if it was a big pay raise, it wouldn't be difficult to talk Sitake into BYU, if you look at his coaching jobs, the BYU coaching circle has been a part of every one of those jobs.
Sitake and KW haven't always seen eye to eye, and even if BYU doesn't call soon, if a Utah HC position isn't a high probability, I am not going to be surprised when he takes a HC coaching position somewhere else in the near future.