I have an A1465 on my bench with a really weird issue. It came in because the customer tried to update to Big Sur and the update failed and split his OS partition into 3. I backed up the data and wiped/tried to install Monterey from a freshly downloaded App Store copy on a USB drive and it fails after 5 mins saying "there was an error while loading the update". I tried installing Big Sur, and it gets further, but when it gets to the part where it boots into "recovery" to install a firmware update, the update immediately fails and the system restarts to the installer screen. I've tried connecting to WiFi and plugging in a Thunderbolt to ethernet cable, both to no avail. Have tried multiple downloads of the OS, multiple SSDs (internal and external). Current SSD is an original Apple 250GB. Board looks clean, no signs of liquid or corrosion. Does this sound like a wonky BIOS chip? What else could cause something like this?