Got a similar problem.
I used shadow heart to venture into the shadow cursed land.
I saw the convoy with the drider but stayed hidden. Convoy waited at the end of the road.
Then I reach the inn and used the waypoint to TP the rest of my party to the inn.
I got the selune blessing and was ready to attack the convoy but that stupid flamming fist showed up and I ended up having to kill all the undead harper.
Now the convoy is gone. And no lantern. Is there any otherway to enter the deeper shadows? All the light spell die in there and my party is getting killed fast with necrotic damage...
at the point you are at you MIGHT be okay using the spell daylight cast on a party member, but that no longer works at the part I am at...