kevin_video: I apologize for this stat block. Somehow "ooze traits" got taken out of the "Immunity" section. And, for the record, there is no 'i' in the name of the monster. It's "Rellumm," not "Relliumm."
I took a base creature, added a template, and then changed its size and Hit Dice and some stats and honestly, the math just got away from me. I had calculated the DCs and Skills before the size change. Basically, the size change screwed me up. After looking over what you said, your numbers are correct and those are the DCs that should be used. The DCs for Horrible Constriction and Engulf are supposed to be 41.
The DC for the Chaos Aura should be 27, as I was basing it off of Rellumm's Charisma (10+11+6=27).
If you have any other questions, please email me at will@adventureaweek.com