you know I wanted to reply to this a few times, simply based on what I found in the Search function of these forums.
the varied Luks problem posts each had an element of your numerous grievances (WLAN, characters, etc). none had them all the same time. very few were 'solved.'
Made me wonder if there was one thing, sequentially, that could be fixed, the rest would fall together?
Who knows? I don't use Luks. Who needs the headaches 😉?
interesting is this:
https://help.getsol.us/docs/user/troubleshooting/boot-rescue#unmounting-your-system
even though it's about chrooting, there is some interesting info on encrypting/decrypting this drive.
tired; two cents; have followed this and feel bad for yr hassles
