There was another thread recently about this, which might help:

https://pinside.com/pinball/forum/topic/system-7-mpu-draining-battery

The only component causing this would be the diode the stops the batteries from trying to run the entire board or the ram chip The diode that blocks the batteries from charging has nothing to do with dying batteries.(just exploding batteries) Measure for voltage on both sides of the blocking diode, this will tell you if there is leakage getting past the diode somehow, If no voltage I would change your Ram chip

Assuming your blocking diode is good (take a reading on each side of it).... What is the imprint on your 5101. Some AMI branded 5101s Williams used during system 7 era consume excessive amounts of current.

2101's are also a pin for pin replacement,,,, but will eat your batteries like Skittles.

Stick with 5101, or better yet, get an NVram if your already dealing with a socket and get those batteries into a flashlight instead.

CM8104P-1 is an interesting part number. That must be a soviet clone based on the prefix. CM601P is a valid cold war era 6800 CPU replacement. I can't find a data sheet, but some posts i found make it sound like it is a 2101.

Rare RAM chip - Produced in Bulgaria, in Pravetz factory where Pravetz-8 and Pravetz-16 (Apple II and IBM PC clones) were made during 1980s