Some sanctuary are shared, with 0 creatures inside
Its because the sanctuary stays active for 2 weeks but dinos only stay in it for 48 hr. So if no one has a dino in it it will stay shared at level 5 for what looks like 4 more days. They reset back to 0 and will disappear from shared sanctuary list.
Sanctuaries are shared with your Alliance for at least 3 days. (or when the 2 week period for that Sanctuary’s availability is completed)
Creatures are returned to players after 48 hours.
If no more creatures are placed, the Sanctuary will stay shared with your Alliance (and empty) on the map for 24 hours after the latest creature is retuned.
The Sanctuary will stay at level (and empty) for the remainder of the 2 week period if no more creatures are placed.