Got your PM and note that you'd already tried to update with WebUpdater. It's not been updated to V3.30 Edge because according the GarminDevice.xml you uploaded it's still V3.00, but no way to know from that if it's hybrid fw that was flashed. I assume that the xml you uploaded is the one from after you tried to update with WU. Is that correct?

Edge 500 also has additional components which flash to regions 5 and 85 in V3.30. The rgn 5 bin is lacking in V3.00. I don't know if the rgn 85 is even present in GVN53 but rgn 5 certainly would be. Rgn 5 is to do with the boot process.

If the unit hasn't flashed the higher V3.30 Edge fw fron the gcd and has remained at V3.00, it probably means that someone flashed the edge fw in some other manner. There may be a type of preboot accessible in some way. Or regions may be flashable by SD commands.

You now really need help from our Software Experts on this. There may be a way to dump and flash regions from bin files with txt commands via SD card, but it will now maybe mean using the Edge boot bin as ldr.bin to do that .... dicey stuff.