I think it can be done even if SQL Cipher is not supporting multiple keys.
Take full disk encryption in multi user environment as an example.
Disk content is encrypted with single master key. MK is never revealed to users and is encrypted with each user personal key. When you access the disk your personal key is used to retrieve MK and MK is used to access the data. This makes multi user access, user management (adding, removing) and password change possible without requiring re-encryption of the data.
Btw this feature is #1 in my personal wish list and would be a huge selling point for the Enpass. Think about what option it would open if single vault could be shared among team/family/group members without revealing the master key.