I tried to get the seat off. I couldn't get it off, because the seat was in the most rear position. Covering the rear bolts.
Fortunately, I managed to get the motor off and while getting it off I saw that the motor in front of it (Tilt movement) is exactly the same. I took both motors off and put the tilt motor in place of the faulty one. Yes. I was able now to at least move the seat forward to access the rear bolts
Took the seat off and dissembled the faulty motor. Completely clogged and burned from the inside. I tried to fix it, but then I noticed that many copper wires were broken off of the core part as well. Too bad, not gonna spend hours on this. Ordered a new (porsche) one for 60 euros.
I put the seat back in the car. Set the right tilt position and then swapped the tilt motor to the forward/backward unit again to have forward/backward working. Swapped the connectors as well to also confirm the control unit is not broken, which luckily is not.
I still wonder what you need to do if all motors are gone. How can you ever remove the seat. You always have to move it to access all bolts.