In my current campaign I'm playing as a pacifist Idyllic Bloom empire and I have managed to find the Ketling systems before the AI colonizes them. I have corralled them with my own systems, but I haven't built outposts in them, because I'm hoping to have the Ketling spawn there. In this situation I would like to attempt to get the new "Fixer Upper" achievement. I'm now wondering, if triggering the achievement requires me to own those planets myself, or if I can vassalize the Ketling and use the Gaia Seeder Outpost holding to convert the planets?