I think the things with dashcams perhaps relates to powering via a (vacant) fuse - in the "olden days" it was easy to do this, now with CANBUS night quite so. In my ICE, I asked a dealer to mark a suitable fuse for my to piggyback onto for a dashcam, which was done, when connected I had all sort of problems with tacho/speedo spinning around, ALL warning lights coming on, all trip meters reset and so on. I checked my wiring/piggy-backing and all was OK as far as I could tell. Asking around on forums specific to my vehicle, I was told the CANBUS was exceptionally sensitive and this is what would happen. Many others had it too.
Anyway, the brakes, I have no idea about other than to say that's effin' scary! When parking my MG, it does sometimes get confused when going from a standstill into slow reverse and doesn't release the "hand" brake and tried to move with that on. It maybe something I'm doing, I dunno.... Sadly these days there's no manual brake handle to pull that you can use to stop the car!