DTB, I think Mercedes does not want anything but their Mercedes alternator charging the chassis battery, so neither shore power or running the generator will charge the chassis battery. Going the other way, they apparently do not have a problem with, that is using the Mercedes alternator to charge the house batteries, which it does. By the way all your voltages seemed to be right in range. Since I have an inverter installed, the panel for that is to the left of entry steps mounted on the cabinet the sink is in, so I get constant voltage displays from that.
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