I had a similar experience with my first Sunken Crypt encounter. It cost me a couple of deaths, I was down to my weakest weapon/armor kit. Light bulb came on, albeit dimly. Stagbreaker (or iron equivalent). Mine enough of the iron to see into the next room but still have some protection. If body pile is close enough to entrance several smacks with the breaker will destroy the pile. Continue smacking and the rest of the spawners will be dead. I did have one case where the pile was in the middle of the room. That required making several attack/retreats before I could finish off the pile. The breaker also gives you knock back so it will buy you some time.

Good luck!