the hack on the DMD controller might be if the "repairer" had issues locating the correct zener diode. you can make the right voltage value with a series connection of multiple zeners. Should be an easy replacement, the main concern is to make sure the voltages are correct at the DMD as some "repairs" increased the DMD voltage or the differential voltage to make outgassed DMD's look brighter.
The cabinet cracks aren't obvious in the images you supplied, but remember these are not new in box so they will exhibit various issues that depending on your skill set can be repaired.
Ball motor might be an issue with the pinion gear (most likely) but can be also a failed motor, driver, motor interface board or just a loose/broken wire. Impossible to assess from 20000k's away. lol.
If the playfield is good with limited wear around saucers, goalie and TV award then most other things can be repaired. It all depends on price and your skill set.