Will Butt is a pretty good player tbh and will likely get some good gametime at Chiefs next season, though hopfully we put that Ikitau money to good use at 10.
I know I'm biased, but I'd have him as more than "pretty good"
I'd be sad to see him go, but I appreciate the difficulty trying to get enough game time to 5 very good centres.
Given a straight choice, I'd keep Ojomoh, Lawrence, Butt & Hennessey, and let Redpath go - not necessarily because Butt is better than Redpath, but because Cam and Mojo are so similar to each other, whilst those 4 all offer something different to each other (not to mention that Butt is an EQP academy graduate).
But these things are never a free choice; contracts come due when they come due; players will have different values to different clubs, and desires of their own.
If Butt goes to Ex, then, like Devoto and Woodbrun - I'll be sad to see him go, but understand, and wish him all the best in his future career.