X2 Mr. Wizard!
JMHO
Meticulously examine every cubic inch of that entire system using a strong flashlight. Aluminum buss bars that have had their tin electroplate burned off are junk. Replace with new. Yes this includes the tin plating inside the wire bore holes as well. The plating has to be perfect.
I would take a dozen unit removal images on your camera or phone and repair to a work bench. Do not repair with automotive wire. Use marine or THNN stranded. Color coded just like OEM. Examine the circuit board and components of the charger unit with a fine-tooth comb. You just may catch a burned circuit trace,bulging capacitor or choke winding that has nothing to do with your current problem but will have everything to do with a future problem.
Bench test. Leave connected and semi-supervised for several hours, before disconnecting and replacing in the rig. Then test it again. You are looking for heat that is inappropriate or current draw that doesn't fit. Be very suspicious of battery charge voltage regulation until it proves itself over time.
After fifty hours of in-service operation, pull the covers and re-tighten all set and binding head screws.
