After searching through the databases of TORHead, I have found several things I think you would all like to see. I believe they were fairly recent additions to the database, as no one had brought them up yet after all the time this thread has been up. A search for the word "Dread" brought up about a trillion results, BUT there was one that surprised me. TORHead reported there being a title with "Dread" in it. I know for a fact that this title isn't in game now. The title is Dread Slayer. http://www.torhead.com/title/145/dread-slayer
Now, I had to figure out where the heck that came from, so I searched for it on teh Googles and it was indicated that you get the title by slaying the dreadful entity (this from DarthHater). A search for this reveals a codex entry on TORHead. I give you.....THE DREADFUL ENTITY! http://www.torhead.com/codex/eNo21aH/dreadful-entity
TORHead tells us that the codex entry is to "Defeat the Dreadful Entity in the Asation Operation".
A secret boss inside the cave? I THINK YES.