If memory serves me right, in series mythology Omega is known for having a self-repair system. Might be true here, might not be, but either way it's still (a scrap heap) buried in Cartenau until further notice.
WhatIlberdMasked Man is talking about, who knows. I'm not yet inclined to believe it's Omega (see above) or a Primal (a plot retread would be kind of boring). What, exactly, who knows... but that's the fun of it, yeah?
From the Echo flashback to their past along with Darklander's far less vague DE dialogue, it sounds like the Warriors of Darkness brokered a deal with Elidibus - kill us and spare their world (for now).