The XPS 9570 and Precision 5530 share the same motherboard. The Precision 5530 is still being supported by Dell.
It’s almost impossible to imagine that a Dell bios update would corrupt your ME, but I don’t know what the repair entailed - it’s possibly another NVRAM issue.
Apply the latest Precision 5530 bios first. That will update a lot, including the ME firmware, and then you can run ME corruption detection procedures that lfb6 spoke about to try and rule out an ME corruption issue.
Can you run the following command from the Flash Programming Tool\WIN64 folder in CSME System Tools v12 r38 and post the resulting bin file: fptw64 -d backup.bin -bios
You should be able to, and then you can examine your nvram volumes with UEFI Tool NE.