Sorry for your loss! Two years ago, I had a bear do similar damage to the door of my South Lake Tahoe cabin (near Fallen Leaf). There was not one crumb of food in the cabin. Sanitary! The bear was just looking for a place to hibernate for the winter.
When at my cabin, which is fairly often, I sleep in my FWC. Twice in the past two years, I have been awoken by a bear sniffing around the camper in the middle of the night. Most recent occurrence was just last month. I have various devices that make extremely loud noise, so that has helped. Like my cabin (when empty of food), I don’t keep any food in my FWC.
A few years ago, one of the Forest Service “Rangers” told us that there are 400 bears living in the Tahoe basin(!). I think that anything that is square and has a door on it is seen by bears as a potential food source.
Again, sorry to see that happen to your 4WC!