If you play a two player game and only the 2nd player 100,000 reel needs reset, will the game reset properly? The 3rd reset relay is the one that pulses the 100,000 point reels for all 4 players. I have you tried cleaning/adjusting the switches on the 3rd reset relay?

So the issue does not happen for player 2 if only the player 2 100,000 reel needs reset. What about player 3 or 4 if the other 100,000 reels end the game in the zero position? Based on your initial description, it is not clear to me if the issue only impacts player 1.

You might try pulling the player 1 100,000 reel out of it's frame while the game is having trouble resetting and applying a small amount of pressure to the switches. This extra pressure might be enough to trigger a reset. Might sound scary..lol