That was definitely my thought. The 6 stories presented here are tragic, and zero is the ideal goal, but I’d want to see data on how their issues compare versus an aggregate of other dog-sitting services (including the “call the neighbor’s teenager who is saving money for a car” approach some here have advocated). At sufficient scale (which it sounds like Rover has), you’re virtually guaranteed to hit some issues where pets pass away of natural causes, or where a tiny number of the sitters turn out to be unreliable or worse. At 40 million “stays,” if the dogs come back happy and healthy 99.999% of the time, that would still leave 40 cases where something bad happened. The real life stats are likely much worse just given dog lifespans and actuarial stats, as you say.
It does sound like there is more Rover could do to investigate and follow up with cases where there might be some fault on the part of the pet-sitter. Even with that I think the precautions you suggest are a good idea.