"Well, I can’t speak to any other brand of battery to battery charger than the Redarc I’m using, but I know for a fact that mine doesn’t back feed DC from the camper battery to the truck. So, as far as I can tell it shouldn’t matter what goes on on either the input or output side of the Redarc."
I thought it said the problem was when the alternator is supplying high amps to the House batt and suddenly the House batt is cut off by the BMS (or a cable breaks?) which is a severe "load dump" that will damage the alternator.
The "high amps" perhaps from the high acceptance rate with Li.
My "alternator charging" (no regen braking with my older vehicles) is fairly low in amps (36ish amps highest seen in the C at first after starting--older style alternator-Ford got a bigger one for the 1992's on), and that current to the House stops when I turn off the engine in the Ford. Doesn't hurt the Ford's alternator. No idea if that is the same thing.
If House is cut off while driving, the alternator still is running the vehicle and the engine battery so it still has some load on it.
