1.x4...the tech was right.
2. The disconnect switch does NOT disconnect everything. Get or borrow a DC clamp meter on your positive battery lead with the switch off and you'll KNOW how much parasitic drain you have. Pull fuses to see where the drain is coming from.
3. To avoid dead batteries in the future...disconnect the black battery cable AT the battery terminal...or use one of these to accomplish the same.
4. You will NEVER know the state of charge in your battery from the battery panel in the coach. You must WAIT 24 hours AFTER charging a DISCONNECTED battery to see actual state AT the batter with a multimeter. The easier but $150 solution is a TRUE battery monitor like those from Trimetric and Victron.
5. If your batteries were dead flat...chances are you damaged them and they won't last as long as they should. A flat battery should be charged for at least 6-8 hours by plugging in the coach in order to get a full charge.