Not trying to start a oil debate but, that's not the best oil for the job. I have used it in my bobcat only because it has a few leaks and I can see using good fluid and have it leak out. I can't say that the fluid had / has anything to do with your pto trouble but it can't help it either. If it was mine I would at least run Kubota fluid or better.
Just curious, why do you use cheap in the Kubotas and NH and use good fluid in the IH? Hytran works great, I grew up using that fluid.