Talk to the party, ask them to cover me, Dunor to accompany me if he wants.
Borrow one of the party's sunrods - if we only have the one left, Galadren will activate the second one that he's carrying.
Throw sunrod into the intersection, and then wait and listen to see if anything/anyone is attracted by the light.
Perception:
Rolled 1d20+9 : 11 + 9, total 20
If nothing appears, sneak down to the intersection and peer into the adjoining hallways and such.
Stealth:
Rolled 1d20+9 : 5 + 9, total 14