Leashed mouflons keep despawning

[Kirinya]

I have tamed a mouflon according to https://ringofbrodgar.com/wiki/Taming for the second time now and they keep despawning on me.
Tamed it in the evening, hitched it to the post, checked for aggro stance before going to bed (none as expected after such a short time).
Logged in in the morning before work (so, ~9 hours after giving the clover) and the mouflon is despawned.

The hitching post is within my palisade, but does not have a fence around it. No other players interacted with the mouflon. I'm a hermit, but have some neighbours nearby.
Does anyone have a clue why this is happening and what I can do to prevent it? Is the guide wrong for W14?

[linkfanpc]

If a hitched animal moves to another map grid it becomes unhitched. It's a bug. Turn on the red grid on your minimap, if your hitching posts are anywhere near the border of grids they're being eaten by bugs.

[Kirinya]

Map grid is directly in between my claim, I made a small fenced area that doesn't cross and the next mouflon is still here. Thank you!

[ThorleifCleaver]

It's also worth mentioning for any newer players reading this that you have to be careful when rehitching an animal after a taming session. You tame, releash, then walk to the post, then hitch. The problem here is that the animal may or may not be close enough to the post to actually hitch when you do this, depending on location, speed, etc. Make sure the system information logs "leashed animal." If it doesn't, the animal will despawn. This is an easy mistake to make, especially if you are on a horse when you try to leash a slower animal like a boar.