Hello everyone, thanks for trying to help!
So, the lot is called "Professor's House" and the creator is Simlicy (sorry I don't know how to get the link). In her YouTube speed build video she did mention that she play-tested it before uploading it to the gallery to ensure everything worked but she didn't mention anything about a crime happening so I'm not sure. She's pretty legit though, I don't think she'd upload the house if something was wrong with it? And no doubt somebody would have told her of the problem by now and she would take it down and re-upload I would think.... It has over 5000 downloads.
Anyway, I tried the "Reset Object (debug)" on the Witness sims but it seems to have made it worse! lol. Not only can I still not ask them to leave, but now it thinks this Young Adult is a toddler! lol. See screen shot below, she now has the "Toddler Needs" option. Also, I noticed the "Remove From Family" option became available after I reset them so I shift+clicked on one of the sims and clicked "remove from family" thinking maybe that would make her leave, but you know how when you select to interact with a sim the little bubble will appear in the bottom left corner and show the face of the sim you're interacting with, well, when I shift+clicked on this Young Adult lady and said "remove from family" the bubble came up with the picture of my newly adopted son's face! lol. How rude, I'm trying to toss him out of the family already. So I canceled that interaction just in case.
Here are a couple screen shots. 1 so you can see how the toddler care function is now available on this Young Adult sim after I reset her, and 1 just showing you that it says Witness above her head.