Move the party to the right to look for a key of sorts.

This is almost sickening.
Knock on the brick walls to see if they are hollow behind them.
They're hallow, but they're not badly built, so it will require some great brute force to break through them.
Nak at jetlok to try to communicate with him

: Nak

: Naknaknaknak!

: Nak nak, naknaknaknak

:
nak nak naknaknaknak nak nak!!!He seems hysterical
Play Song of Healing to open the door.
Or play it backwards to summon BEN and see if he can open the door.
I take it that's from legend of zelda right?
Well video games don't work in real life.