My third R4S is a newer one without this tripod hole ... although I am not aware that they changed anything from a hardware perspective, except for this tripod hole in the case. I ordered it in July. It boots and is also able to reboot.
I know it is quite an ask, but it would be absolutely terrific if you could get an UART cable and provide a serial log. Otherwise we might not be able to figure out what's going on. As said, if I ever see this behavior again I will happily provide the log, but at this stage I can not reproduce it with any of my R4S.
We should probably also move this discussion here.