Talk to father uhrney and he'll tell you that you have to pay for the key. (If you inadvertently burn the crucial, there'll be a respawn in a chest at the east corner of this area ) "use" the unholy leather on the unholy key, then use the RS gold unholy coated key on the molten lock. This will free father uhrney, who will then extinguish the fire using a prayer. Talk to father uhrney and he will tell you that they captured him to get a special package he had for the priest at lumbridge, and he'll tell him that he delivered the bundle to his great friend magician mizgog in the wizard tower once he heard his captors were coming .
He will give you his promised 2k plusd another 30 for vessel fares. Go back to port sarim, and make your way over to the wizard tower. Speak to magician mizgog and he will tell you that father uhrney said you're coming. He will give you"wrapped Package. Duplicates cost 7.5k. Bring the package safely to the OSRS buy gold priest, who is waiting for you at the church. He'll then ask you which god you encourage; Guthix, Saradomin, or Zamorak.