https://drive.google.com/file/d/1OC6qsnmpX9tMUJb0qxeLb4d776oKUQ0i/view?usp=shari...
Here is my save of the above situation
https://drive.google.com/file/d/1lfwtCJMTR3kWpKa4312B0Y_pjDeVaEas/view?usp=shari...
And this is my save on the previous day before assign manpower, with my tech bouns, Asterion and Kota, it sould be done.
I have try it again a few times, the result is quite interesting.
If I directly send Luke to explore without messing the R&D, reseacrh will not complete.
If I switch the role between Luke and Kota, then reseacrh will complete and Greta will appear.
When I dismiss Kota or Asterion and let the other one do the research himself(with my tech bouns which is enough to reach 5 and 5) , reseacrh will not complete too.