First of all it's decryption fix for stock MIUI, secondly decryption was and is working on xiaomi.eu mmx etc and you don't have to mount system and vendor
There's still not a single Custom Recovery that supports Android 12 that's why. Just downgrade to Android 11 or live with recovery not decrypting your files.
both phones have been set password and upgraded from android 11,but only one can decrypt data. thats the case that surprises me. I tried remove password from the one cant decrypt data still no help
Sorry to hear. It's still beta i'll try to fix that in future updates. Thanks for your feedback!