Very strange. Using your TWRP image it is not possible to decrypt on my Poco M3 with the latest EEA stable ROM. With just the modification I said, TWRP asks for the password and decrypts it correctly.
This is not something easy to do (at least I don't know how, but if someone could help me, that would be great!).
#include <std_disclaimer.h> /* * * We are not responsible for bricked devices, dead SD cards, * thermonuclear war, or you getting fired because the alarm app failed. Please * do some research if you have any concerns about features included in this ROM * before flashing it! YOU are choosing to make these modifications, and if * you point the finger at us for messing up your device, we will laugh at you. * */
- fastboot --disable-verity --disable-verification flash vbmeta vbmetaname.img - fastboot flash recovery recoveryname.img