Does not matter what I do, Wilhem seems to have the AI turned off, he does not follow the group and does not respond to combat, he keeps static. No matter if I change any option in the cotterie, it does not work. I have even use the console to turn on/off the AI in game but it does not work. TAB on/off, right click in the regroup button. Nothing.

I need to use him as leader to make the game playable. ever.

Any idea? It all started when once he died and I revived it with a scroll, but It happened to other companions and I had no problem at all.