Congrats on the find, took me a while as well, tho yours appears to be really nice.

I have a number of EM's(not all set up) and I've found that the EM Tech forum has a wealth of info and a better place to find your solution.

I will share that that there are at least 3 things possible and narrowing down is first step.

Is the ball kicking out of saucer? (eject coil not firing to clear and unload saucer switch)
Does this happen when you collect Silver Bonus in other saucer? (Silver Bonus Relay)
Does this happen when any other 1000 pt is scored? (1000 pt relay)

I'm not sure if there is a Stepper unit involved, if so and it's not Zero'ing out on bonus countdown( a switches closes which stops the pulsing of the 1000 pt relay) then it will also do what your saying.

And get a schematic, they are oh so helpful.

I think we all like to "pile on" when it comes to shipping from Marco!

Meanwhile, while your waiting I busted out my Schematic and now that I know nothing is kicking out, I looked for the common denominator( See Pic 1.) I've pointed to the circuit that handles all saucers and they all come thru a score motor switch, 4C . The other photo shows where C is in relation in the switch stack to the #4 score motor disc, along with wire colors.

I would check continuity thru that switch as you manually turn the score motor(machine unplugged!)Alligator clips work well if you can isolate them from touching any of the other solder tabs in the mess of wires. A wise EM tech on this site told me to always check with the meter not the tone.

Since it was working and just stopped ejecting, I would check for a cold or broken solder joint between the switch the the Jones plug connector to relays all the way up to the eject coil. But since they're all not working, it's likely not up in or past the relays.(Pic 1)

Good luck and machine unplugged!

saucer eject circuit (resized).jpg

score motor (resized).jpg