hello daniel.banar,
this is an incorrect approach for testing rootfs redundancy.
the retry_count decremented is triggered by software (i.e. warm-reboot).
unpower or using a physical button is cold reset. you should have warm reset, such as $ sudo reboot commands to reboot the system.
you may see-also similar discussion threads, such as Topic 301119, or Topic 332725 for reference.
is it a must to stay-on JP-5.1.2/r35.4.1?
is it possible for moving forward to the latest release version (i.e. JetPack 6.2) for verification?