Certainly sound like it... if you can test for continuity from both ends of that wire, should tell you if it is the same.
If the trombetta isnít seeing voltage from the house batteries, it will think they are dead, and not connect the batteries together to charge from the alternator... that is done to protect the chassis battery in event something is wrong on coach side.
I suspect what really killed your batteries was them not being disconnected from coach when you press store. They will only last a few days with the normal idle draw of the coach. Whether that is the same reason or another problem, Iím not sure.
Not yet retired...
Florida (Michigan transplant)
2014 Hurricane 32A
2000 Infinity (previous)