It probably started in the underdark and the goblins only recently abandoned their god for the absolute. Goblins aren't the smartest so they could have been convinced by a few nice presents (which they obviously got)
Let us return the thread a bit closer to where it started: Minthara
She would be the ideal character to explain some of these things. Unless true-souls automatically know everything about the absolute and there is no need for them to be introduced to anything. Which would indicate that you were not supposed to become one of them

I sometimes use thought experiments. I don't necessarily believe in every idea I post for discussion on this forum