I reach my conclusion simply based on what an activation is. The critical part is the question you highlight.
If it’s a clear turn, are you activating? I don’t know.
You definitely, 100% cannot activate any models on a clear turn. Even though you can do lots and lots of things on a clear turn, none of it will be activating a model.
(Caveat - A Last Man Standing gets to activate at the end of a clear turn. But even he wouldn't get to remove fatigue from manipling, because you have to do tactics before you can activate him.)
Activating a model means having access to its fatigue store, so to speak. When you are activating, you get a free move, and you can spend up to two fatigue. That's what activating a model means. if that is not what you are doing, then you aren't activating a model.
That's the intent that I read from the rules when I read them, and that's what I base my interpretation on.