I did come across that, but on their respective pages none of them tells you in detail about what to do to get there :( Like do I need to have destroyed the cult beforehand or not? Do I need to keep giving the imp Essence up to a certain point before I can tell him his name?
oh, well then this might help you instead: https://dawnofcorruption.wiki/index.php/Endings
For the imp you need to be submissive to the imp fyi