I have 3 of the IM pumps. Never used them. I always throw in a Sicce of appropriate size. But, Let's try process of elimination.
Pull the impeller and check for anything inside the impeller socket and on the impeller/magnet, that could impede movement. If you see or feel anything there, clean it up with sandpaper. Carefully and use a very high grit, 440.
Also, try running the pump out of the water with nothing on it. Just the pump and the impeller. Just for a moment to see if it will fire. If it won't run without the basket and cover, your problem will be in the pump or controller internals.
So now let's try the pump. But put it on your other controller. If it works, you have a bad controller. If it doesn't work.
Put the known good pump on your bad controller. See what happens there.
At least after that you will have your issue isolated to one of the three pieces.