I agree. Rolf is heading in the right direction. Here is an embellishment:
Start a 2-player game.
Don't let the ball roll on the playfield, but manually actuate both a 10 and a 100 for player 1, ball 1. (Manually click the relay is one easy way.) Do NOT score any 1s!
Drop the ball in the outhole so that the game advances to player 2, ball 1.
Hit a 1-point switch and continue with the analysis suggested by Rolf.
Now you know the difference in behavior between the player 1 1-point reel and player 2's 1-point reel. If the problem is an end-of-stroke switch on a score reel, you'll probably see a difference.
If you can't complete the diagnosis, bring the game! Experts will be available.
.................David Marston

So the 1-point relay is trying to actuate either the player 1 or player 2 1-point reel and not causing that coil to pull in? Now you need to identify the wire color of the wire from the 1-point relay that goes to those coils. Somewhere along that path, it goes through a stepper-unit disc or switch to choose between player 1 and player 2, but if both players behave the same, then the breakage is in the part that they have in common. I say "breakage" because the power is not getting to a place that it should be. Try to follow that wire along its whole route, although the two endpoints would be the main suspects. I wouldn't expect any connectors along the way; everything should be in the back box.

As a separate issue, you seem to have a 50 point switch stuck closed somewhere. Check all the 50 point switches.
.................David Marston

Try Tony D., Dave Metrando, or me. Tony has a team and can pick an available EM expert from that team. If you have the schematic, be sure to bring it.
.................David Marston
(who is wearing his Team-EM shirt today)