Troll Shaman, dark elf warrior faction
 

Like a rabbit I die if i play alone. How bad will hunting in Crushbone hurt a troll shaman by having no DE war faction?

I strongly don't recommend it. Do you want to go to grobb every time to use merchants? (other than bankers)

I know you can kill the wood elf guards to improve dark elf guard faction but i'm not certain on other neriak factions.
just go to kurns tower and skip crushbone.

For Dark Elfs the faction hit is specifically for the warriors guild (Indigo Brotherhood?), so would be very unadvisable to thrash it in Crushbone. Sucks I know, try BB or Kurns instead

The warrior guilders stay almost exclusively to their arena tower. You can move around the rest of the town basically without bother.

OP is a DE warrior though

OP is a troll shaman... anyways - banking, selling, buying food/drink etc will all be fine in Neriak and you’ll literally never find an indigo brotherhood unless you look for them

So having made this mistake personally, it sucks. You still have free reign, more or less, of Neriak but if you intend on doing the snare inny necklace, AVOID CRUSHBONE at all costs! The final tier requires heavy interaction with Indigo Brotherhood mobs in LFay.

Does killing slaves in CB counteract this "problem"?

From what i've found, only the WE slaves will bump IBro faction and good luck getting a quantitative amount of those to pop.