Check score motor cam 5 switch B . The top part of the switch is the normally closed part of the circuit that keeps the relays closed in their hold circuit until cam 5 drops the switch stack and opens the hold circuit. If the switch isn’t normally closed properly the hold circuit will open at any time.

In one of the videos I have noticed that points aren’t scored on the B drop target. Drop target scoring involves 2 normally closed switches . Whenever a drop target is in its up or dropped position either of the normally closed switches will be opened. It’s when the drop target starts dropping is when the 2 normally closed switches will close and award the score .