OP is quite right that this bug can happen with Razorback. For two games in a row out of the four I've done this time around, it would sit at no health on all four legs but refuse to fall, and no additional Bursa would be able to take it down. Host migration seemed to have fixed the first run, but as I was the host for the second, I cannot say whether my departure (and subsequent host migration) fixed it for my teammates.
I don't believe I've encountered this before, so I'm not sure if it's been an issue all along; but I can nonetheless confirm this is an issue and OP wasn't just imagining it.
