I'm new to cocktail pinball machines, this is the first I've ever seen. Looks very, very nice. Awesome.

I'm curious to know if you managed to get a dump from the CPU with the eprom reader now.

Let's see, I see you're fairly handy. You made those little patches and checked them with your meter. In addition to the CPU test, here are the things I also wonder about..
-Is it not possible to find *any* documentation about this machine or perhaps a similar one that could tell about any 'beep codes'?
-Confirmed *all* voltage rails on cpu board are good? No shorts, all correct levels?
-Confirmed all chips in the area of the NICAD leak and elsewhere are getting the correct voltage on their power pins? This may require googling pinouts. Just be deliberate and a little careful when probing pins not to short pins. Let's not make any new issues

Beyond that, if you can get hands on an oscilloscope, even an older one, you can also start confirming that Mr. CPU is getting fed with some clock pulses. Not critical to confirm the rate at this point. Crystal(s) working or not.

If you're not going to get any insight as to the circuit operation in detail, this is where you start.

GOOD LUCK! This is worth the effort!