Ok I feel like I have at least some useful information to move forward. I also attached photos of the power supply. I removed the new U39, put in a dip socket and then put back the old U39. Unfortunately the same overloading occurs now on the old op amp as well. It didn’t do this before so maybe I messed up the VCA putting that replacement in?? The CEM3360 is reading +1.9Vdc on its output pins with volume slider up so I think I’m ok there. I also rechecked pins 6 to ground and pin 9 to ground and both read zero like they should. The unfortunate part about the removal of the TL084 opamp U39 was a broken trace! I followed it to C81 and was able to bridge it (one photo attached with red marking and one with the bridge in place). The pin on U39 leads from c81 to a U39 pin then goes to a small pad sandwiched between c118-121. I tested U39 after bridging the trace and am getting a solid +12Vdc on pin 4 and a solid -12Vdc on pin 11.
I tested the transistor Q7 to the left of U39 and was reading -12Vdc on the input and -5Vdc on the output. Another note, the keyboard originally would make a little blip sound powering up and down but now it’s more like a longer squeal.
Regarding the power supply, the skim job I did caused the heat sink to get crazy hot so I removed that and rechecked voltages and I’m back to normal minus the ongoing small over voltage which has been present since day one. So maybe the pad I tried to fix didn’t need fixing and the underside pad still worked.
To recap, at this point I’m not sure why the audio output is still overloading after putting back the original U39 when it was working ok before. I need to go back and check for any unwanted voltages. Thinking about ordering a Cem3360 clone and a new TL084.