Tried the MicroSD with high-speed USB adapter, but it gave a notification to "Remove and re-insert USB drive for faster speed". I did exactly as it said, but it just gave the same message again. I left it alone to see if it would still work, but it didn't even try to record any sentry events. I tried using it through a USB hub, and it didn't give the notification message anymore, but also still wouldn't record sentry events.
I eventually swapped back to the original Tesla USB drive provided, but now that isn't working either, having the same disconnection problems as my bigger & faster USB drive originally tried.
I'm at a loss of what to try now, so I'll probably need to schedule a service appointment.