Did you manage to resolve this?? O’ve been having the same annoying issue as you (inaccessible boot device BSOD) I tried everything i read you did with the same frustrating result. I noticed, that whenever I rebooted the machine on macos the thunderbolt drive didnt show until I unplugged it and plugged it back; so I thought maybe the imac (im using a 2019 imac, not mbp) was turning it off or something. I took my thunderbolt drive (not an X5 but an addlink nvme ssd with a wavlink enclosure) (way cheaper) and using my old hard drive cloned partition, I simply pressed option on the apple logo, selected efi boot and two seconds (or more) after the windows logo appear, i disconnected the thunderbolt drive and connected back in, and windows booted. I dont know why or how but it did work. Of course, at least for me, this is a “less than ideal” situation and if you ever find a way around this I would be very thankful to you. I hope this helps, you are the first person i find with a similar problem, and also as you, I read and performed thousands of tutorials and help guides with no luck. Please feedback to me
No, sorry. See the commend above yours for TwoCanoe’s testing. Strange that hot plugging it makes it work, but that’s not a solution I want to use. The thought of ripping out the boot drive and reconnecting it while it’s attempting to boot just screams corrupted data to me eventually. Interesting fix though. Might be something about how the computer recognizes connected drives at boot vs. newly connected drives.