[sourdough]

I think the back story on how 2 Dragonfly lithium batteries got installed in the RV. Did the dealer just "throw those in"? I've never heard of one doing so. Did OP ask them to install them? If so, and that is all that was requested, the dealer is not at fault. I'm sure they thought the owner was going to do the necessary upgrades to make them compatible. When requesting upgrades from a dealer the requestor needs to know everything required, or ask, or they will get exactly what they asked for whether it works or not. Don't know that it's the case here but something is amiss with those batteries being installed with incompatible equipment by a dealer as "the plan".