CY... given that the batts were fully discharged & probably damaged somewhat, suggest that when you charge directly to the converter from household current, you take a minute to check AT THE BATTERY TERMINALS with a voltmeter that you are getting over 14V since the batteries are depleted...give it a couple of minutes before you check. After an overnight charge, your next reading should be around 13.2V with the charger on.
After you've charged...unplug for 24 hours with the battery switch set to off...then check voltage again. Should be 12.6 if like new. 12.4 shows loss of capacity. 12.2 indicates you should think about replacing those batteries especially if you do any boondocking.
Of course...before doing any charging...check and fill the distilled water in each cell so you don't do further damage.
2015 Georgetown 280DS
2014 Vespa LX150 2014 StellaAuto 125