If I'm reading that correctly it takes 7.4 hours to go from 50% to full with 120v, if using solar it probably wouldn't get full and sooner or later your looking for a verrrrry long generator time or looking for hookups.
Even if his charging isn't working correctly it's a fraction of the time and if he had solar and properly size solar for that 1 battery he probably would never have to plug in like in my setup. 1,073 days of fulltime use was my longest stretch between a plug in and 45 days running in a PSoC before getting back to full off of solar. I don't believe you're doing that with wets/ agm without severely shorting thier life.