Before I entered the room where King Olaf is found in Tending the Flames, I left my companion in the room with the combination door. After the king and all the draugr were dead I tried to return to my companion and found I was blocked by an invisible barrier where the entrance tunnel opens into the large room where the battle took place. I was able to pass through only by using TCL in the console, but my companion still was trapped behind the barrier. Is there a way to disable the barrier to retrieve my companion and the loot I left with her? Is that barrier a bug or a "feature"?

this is a quest from the bards college.

have you tried to reneter the front door of the crypt. i found that usually when my companion is lost i can have them with me again just by going through a door.

Go outside and fast travel. I'm pretty sure companions teleport to you when you fast travel.

Fast travel doesn't retrieve companions if you asked them to wait.

Strangely, on my PC, there was an Apprentice locked door where the OP encountered an invisible barrier.

The ghost I followed through the dungeon disabled that barrier for me, though I didn't try to go back through so not sure if it went back up again after we passed through.

Click your companion, (tcl through the barrier if nessecary), then type: "moveto player" on the correct side of the barrier and it'll teleport them to you.