I was up at Wild Haven (Manton, MI) for a couple of days over the holiday. Wildman seems to have rebounded well from some health issues in the last couple of years and is hard at it redoing a bunch of the newer back "Little Bigfoot" course. It's not ready yet but he gave me the okay to mention that he's planning on getting it back up and going.
The original "Yetisburg" is fully playable and open. There is one new pin placement on Hole #6 next to the freeway due to erosion. The basket is now tucked into a grove of trees on the right and makes that upshot more interesting, in my opinion. This also brings the O.B. property fence closer to the action there.
He is installing some sort of dock material as alternate tees all over the place too, in addition to the cement long tees Yetisburg already features.
TLDR, the original 18 at Wild Haven is open and in good playable condition right now and the township is allowing camping once again. He has his donation yellow tube there, and if he's on site he has a nice pro shop there too for your perusal. Any questions, of course, contact him.