Treasures of Utzaal - Forced to Portal Out (Bug?)

I'm not sure if this is intended but my friend and I had to use portals to zone out after defeating the boss.

1. Defeat Boss
2. Loot hammer
3. Try to walk "North" back to entrance of arena
4. We hit the wall of lava that has hardened (I assume this is intentional)
5. We have to portal out

I'm sorry if this is erroneous but figured I would post just in case, given other people's issues with the hammer not dropping.

The same happened to me just now

This has always been the case and as far as I'm aware it's intended, though very strange layout for the map.

The map in general is pretty weird - there's also a checkpoint halfway through the stage next to a lava pool which goes nowhere. Feels like you were intended to drain the lava from the boss fight and return for a secret, but there's nothing there.

Stage probably needs a little love.

I noticed those 2 check points as well, I was going to go explore that area after the boss but it forced me to portal, kind of odd.