@Tuna
Here’s a workaround you could consider – give the camera an in-car WiFi network so it doesn’t become unhappy after 1.5 hours of recording. I use a HooToo TM01 for my off-grid recording. It’s a tiny AP combined with a 6000 mAH battery. That gives me over 12 hours of run-time. You don’t need the battery since you have the cam connected to your auto battery, but the AP function might solve your problem.
Another option is the GL.iNet GL-MT300N-V2 mini travel router. Power it the same way you have powered the camera. Configure its WiFi to have the same SSID as your home WiLAN. The cam will associate with the GLnet network. Of course, it won’t have connectivity to the internet, but the existence of the WiFi connection might be enough to trick it into continuous recording to the SDcard.
As for your question about how long it takes to get a response from Wyze: don’t hold your breath. From my experience, it could be a couple of months before you get a reply from tech support (not counting the automatic robo-reply). Even after you make contact with a tech support human, the time frame for a firmware fix is indeterminate:-(