That's kinda not surprising. Only heart disease and cancer outrank accidents as causes of death in the US. Cancer patients usually die in hospital or hospice. Heart disease can come more suddenly, and I'm sure there are quite a few heart attacks in national parks, but it doesn't surprise me that there are more accidents.

You might have a stroke while at the park, but if you're going to die of diabetes, pneumonia, or COVID, you're probably not going to do it on vacation.