When you unplug the camera in the middle of writing to the SD card, lots of bad things can happen. Missing frames is just one of them.
Why incomplete clips? It’s because not every frame is written immediately to the SD card. A few are kept in a memory buffer, and when that buffer is full, that’s the time it’s written out to the card. Abruptly cutting off power, you lose contents of that buffer and that part of the clip is also lost.
I thought I read somewhere in here that it writes one minute at a time? Like the above post and your testing that sounds right. It records for a minute and then write when that finishes, whereas if it looses power before that minute writes, that minute is lost.
Eliminate the problem .
Plug one of these in you will have lots of plugs available , they won’t have to unplug the camera to plug the phone in or something.
I can see how you missed the point but “I want to be able to identify who unplugs the camera”. Some people will just unplug the camera because the want to not need to.