Had my first ebike flat today. Still not sure what the problem was. When I'm on the road I swap in a new tube and examine the flat at my leisure when I get home. This being my first ebike, I bought a new KLIC HP Gauge And Co2 Hand Pump, threw in a new tube, a couple of CO2 cartridges, and I was on my way.
Prior to my ebike, my only experience changing flats on the road was my 700c road bike tires. It's a slightly different skill set. Much easier to get a tire back on the rim of an ebike, IMO. But I had never used CO2 to fill a tire before. So the combination of first time factors made the experience take (for me) longer than it should. I am not the greatest bike mechanic in the world, to put it mildly. Fortunately it was a beautiful day, and my endorphins kept my frustration in check.
After going through the experience, my recommendation is this: Do your first ebike tire change at home. There is always a bit of a learning curve when doing something for the first time. It's a lot better to learn what you're doing at home, instead of when it is dark or raining. If you've never changed a tire before, learn at home first.
My local Pedego dealer is now carrying these. I haven’t gotten them (they are pretty spendy). What I did do was get the most flat resistant tire I could find when I needed new tires, Schwalbe’s super moto X. Great tires. No more flats. I don't know if they make them in sizes for fat tire bikes.
I think your parents have great times ahead on their new ebikes!