I tried inviting and interacting with the scientist. Then I played as the scientist while she was on a visit, and I moved her household to another lot. Everything was okay; I even had a shift at my work. Later, I wanted to exit the game to reintroduce all CC and mods to the game. I didn't intend to save the game because I would lose all CC items, but while in the game, I chose the 'Exit game' option, and I saw a window I had never seen before (Cannot save). I am attaching the screenshot.
Ultimately, I left the game without saving, as planned, to add CC and mods back. I planned to do the same - invite the scientist again and move her to another lot. However, I couldn't do this because an error occurred.