The batteries are brand new as of less than a month ago, as when we bought it we had the same issue and thought it would be the batteries as they were original from 2003 so replaced them.
Is it possible we bought the wrong batteries and that could be the issue? Knowing now that the tech that sold them to us told us to put the trickle charger on the house batteries instead of the chassis battery, I am wondering if perhaps he did not have the knowledge and sold us batteries that would not work for our setup, or is that even a thing?