I would get my info together on the battery replacement if possible, call Interstate and speak with 1-888-772-3600 M-F 8:00 a.m. - 5:00 p.m. Central Time and let them know what has happened as a company then contact where you got them and tell them.
Inform them that you are in need of a fix prior to returning and see what they say.
I was on the road last month when my inverter burned up. Needless to say I was boon docking and had more days to go. I ended up chucking the warrantied inverter due to the send it back, let us look at it to determine failure and send a new unit fix--wait. I bought a new one. Perhaps you will have a better time of it with batteries.
2015 Ford F-150 3.5 Ecobeast 3.55 Lariat