The Guild Master, Lucious Graveburn, was not aware that there was a Mine near the temple. The Mine was crated by the Crag Dwarves in the mountains that are technically within the territory of the Spartes.
The mine has been kept secret for a long time and provides Mournlode. The party eventually finds this mine and it turns out it was deserted. The excavation at the temple nearby caused earth elementals to rise from deep within the earth and they scared off the crag dwarven miners who fled to their encampment a couple hours away. The party investigated and the druid (Who can speak Primordial) was able to access the situation.
They found the evil elemental, killed it for the protective earth elemental (who couldn’t wage a fight on the other because they are technically both in service of the Plane of Earth). The party assisted and found a secret entrance to the temple that they had to blow through with explosives. The earth elemental wished them goodluck in calming the dark forces within the temple and sealed them inside. (The crag dwarven warden was a dick and basically left a bunch of his minors to die, but that is a smaller tale and can be left out.)