Yeah, I definitely get that it is not a priority. I'm not blaming the devs for that, I admit I phrased that poorly.
It's just a bit annoying when you do get the bug. But yeah, I imagine there's either some issue with misplaced AI bounds or some issue with a geometry interaction that causes the Jackal to be pushed to the top of objects. I referenced some other occurrences of this bug in my own post on it and there are at least a few more. Some don't even have it getting stuck on specific geometry, just floating and unable to be finished because of it. They could be unrelated bugs but either way, the requirement of standing directly in/underneath the Jackal is causing problems finishing it. Maybe just allowing it to be finished in mid air would fix the bug while not having to do an in depth investigation into why it's doing what it's doing as of yet.