I realize this reply is a few months too late maybe, but I just want to type this here to help anyone who may still be lurking around this forum. :)

Well in your situation I would say you should reload back before you talked to the Tchortists. Basically you will need to wander into Faceless terroritory a lot for essential items, and they have endless respawns, so if you can keep them friendly (or at least neutral) you would have a much easier time. It is possible to be friends with both the Faceless and the Tchortists (and even finish an easy quest for Tchortists), you just need to visit the Faceless *first*. The Tchortists have a weapons shop, while the Faceless provide one time supplies of ammo and meds.

As for general advice, avoiding the effects of creeping dread and Eye of Tchort is perhaps most important. The annoying Tchortling minions only spawn once the creeping dread debuff adds up to 20 stacks and turn into Eye of Tchort. Those debuffs will continue to add up in the Hollow Earth area, except in some underground bunkers, so use that to your advantage.

Your main purpose in the deep caverns is to open the gate to tchort and killing it, and without going into too much detail the things you need to do are:
1) Restore power to various sections of deep caverns, by going through Arke power plant.
2) Find repair parts for the gate (scattered throughout deep caverns), and either repair it yourself or find help.
3) Find something from the mushroom forest to remove the biomass on the gate.
4) Find a keycard to open the gate.