Ah that's it then. I Assume you need to finish Haiden's research adventures on the board (there are 10 of them, each appearing one after the next is complete) once all 10 are done, you should get the next mission in Dregan.
If you're using a save that was made prior to v.0.22.x (that version was released back in August 2025) then you need to start over to fix your save unfortunately. It was stated before that those were not compatible with the new version.
But I completed these 10 tasks a long time ago, and Dregan didn't appear on my map