Bootload Errors

I am trying to figure out what is causing this issue. I have 16 RPi4's installed and 2 devices boot to this error "occasionally". When it happens, sometimes I can reboot the Pi and it boots fine. This particular image, I have not been able to reboot it into a functioning OS. Another device, it works sometimes and doesn't work other times after rebooting. I originally had this issue when I added another FAT32 partition to the mix. Removing the partition fixed the issue (although, I did notice the error a couple times beyond this).

Hm. This appears to be degenerative. If I flash an SD with "the image", it will boot well. Over time, as the systems are hard-shut-down daily, sometimes multiple times, it may or may not eventually show this screen--which appears to be corruption-related? Maybe Sometimes, however, power cycling again will resolve the issue--and sometimes not. Sometimes 4 restarts will resolve the issue, but sometimes not. I'm trying to get to the root of the issue so I can plan a sane recovery, but am not too well-versed with these types of issues. Any thoughts or guidance? Things you would try/look into? The hard-power-cycle is currently unavoidable. Our next circuit will have supercap to allow a natural shutdown in hopes to alleviate this issue (or switch away from RPi's altogether in favor of a different microcontroller with a built-in microprocessor. Deployments would be a lot simpler with this new approach. But until then...