Complete all the missions in the science division for each island. They are pretty easy especially if you get five stars on the island by that point so you can just focus on the mission itself.
I had mentioned this not unlocking for me. If that would happen to you just reset an island and complete the mission again. I reset the first island and completed that mission and it unlocked right away. I’m not sure if resetting the island will cause any other achievement issues (five stars) so just come back to it after you complete all the others. I know it will not reset the database however.