Same problem on Xbox One.
First cat I ever placed on an official Sipta server was invisible while placing (I waited a long time before I finally decided to place him anyway…) and remains invisible every time I log in to play. I can get the cat to follow (he’s marked as following but seems to do his own thing & doesn’t go where I point) and even level up.
However, when I placed another cat on a different official Sipta server just an hour ago, the cat showed up fine.
None of my other followers have been invisible for any length of time.
Basically some cats will be permanent Cheshire cats and others will work as…expected.
Latest update seems to have (mostly) fixed this on the affected server. Until this update, almost all the cats I had waiting in a box wouldn’t appear when trying to place them, since I knew they wouldn’t show up after placing them either, but one cat did work.
After the update, all those broken/invisible cats were showing up and could be placed - except one.
Still, I’ll take it.
The strange thing was, this bug was not a problem on a different Sipta server, even when getting the cats from the same location and placing them in the same location. 
I still didn’t figure out how to get a cat 
. I play on ps4 and the last days only Siptah again and i kinda lost this feature of the game. I crossed almost all the map multiple times and many camps, no sight of this animal . Who knows, maybe one day…