I opted to go to the Grove of Reflection first to get the branch to remake Sheogorath's staff, but nothing happens when I reach the obelisk. I had a peek on the unofficial wiki and it says that the corrupt clone should spawn as I approach the obelisk. Trying to activate the obelisk didn't do anything either. Is this bugged or did I have to go get Ciirta's eye first?

It has been a while since I have done SI but I would think you have to get the eye first. try that

I just went and retrieved the Eye first and it's still not appearing :facepalm:

edit: I just had another look at the quest info on the wiki and this quest update did not pop up when I entered the grove as I believe it should have: 150 I've arrived in the Grove of Reflection. According to Dyus, I must locate the Tree of Shades and find a way to reveal my true self before I will be allowed to take one of its branches.

I tried setting the stage to that point and the clone still won't appear. I looked up and down the console command list and didnt see one to force the npc/monster to spawn... does one exist? and if so what is it?

realod a previous save

enter melchar from another location

since your on pc and can use console just add the journal entries or the clone in the area your self ?

I did try adding the journal entry manually. I found elsewhere that modded armour will glitch it but it still didnt appear when I changed into normal Oblivion armour. I couldn't find the console command to make the clone appear. I think my most recent save is beforeI got the eye, but i"ll try it anyway.