I'm not sure why changing the entry in /etc/fstab would resolve the issue of the missing passphrase query in the first place. /etc/fstab is only read after successfully decrypting your encrypted file system and any change in there will not be reflected at boot.
I'm not sure why changing the entry in /etc/fstab would resolve the issue of the missing passphrase query in the first place. /etc/fstab is only read after successfully decrypting your encrypted file system and any change in there will not be reflected at boot.