Why yes. I am offering you the direct site for IRV2. There you will find direct assistance for troubleshooting by phone in real time.
2014 Thor Challenger 37KT Owners iRV2 Forums
Here is the another. Not the same as above.
2014 Thor Challenger 37KT Owner Thor Forums
My assessment will be the automated transfer switch is not working. If the battery pack is below specified charged levels. The system has a protection circuit not to allow the transfer from the grid to isolation switch. When the charge is achieved to satisfactory levels. Then it will function.
It is possible you may have a shorted cell in one of the batteries preventing the charge to be successful. I would observe the water levels in each battery and every cell. When full there is a mirror like image in each cell designed to indicate the level. A run down battery will have very low levels at either end of it. The hydrometer is the best way to see specific gravity. When found then isolated you can remove from the series.
A blown fuse or tripped breaker protects the downstream equipment and the power control board.
There should be a shop manual somewhere in the RV. Customer service is available at the links offered. Fare. well.