If you do go non rechargeable* its probably best to make sure you have spare batteries (located next to the lanterns, only for lantern use) for when they inevitably aren't changed and run out of power when you need them most. Probably teaching someone to suck eggs but worth pointing out...
*Not that rechargeable are any good if they aren't recharged to full every time they are used!
No, you are correct, she's 86, obv cognitively not as sharp as us, I`m trying to get the best solution, that includes ease of use/avoidance of any issues/config etc that *may* befuddle an 86 yr old non tech savvy in the dark.........its not so easy lol. One of the reasons for using eneloops being they hold charge for long time, AND I have some and charger.