Mirphak logged earlier on the shard as I was going away and we had a little chat. I told him that we couldn't do the green and red marker missions.
He proved me wrong and he sent me a picture with this statement: "Un marqueur à Descent, je ne savais pas!". Me neither LOL I didn't know there was such marker in D'ni-Tiwah.
Curious as always I decided to make my own researches. I grab 30 of them (15 green and 15 red) but I made sure I was able to see all of them so for the last 6 I just went to their locations and saw them and waited for the last (the 6th) to grab it to make my 30 markers.
So if you are aware of the official MOULa walkthrough, you know there's 33 markers spread in D'ni-Rezeero (2), in the neighborhood (7), in D'ni-Ae'gura (city, rooftop and balconies) (23) and in Sharper's Office (1).
In MOULa, we can find a 34th marker in D'ni-Ashem'en district:
Novelty in gehn 3.0, we can find a 35th marker in D'ni-Tiwah (thanks for Mirphak to have informed me of its existence):
So there's no excuse to not find at least 30 markers! You have more choices than ever!