Pantheon Vessel Possible Bug

Not sure if this is a bug, a UI issue, or a skill issue.

I have a 5 slot map device.

I put cold river map, with a divine vessel and some scarabs in, ran the map, killed the bosses, when I went back to my hideout, the "new vessel" was not in my map device; but I should add that I pre-emptively filled the slots in the map device for the next map, so I'm not sure if I just made it so there was "no room" for the new vessel to be created.