This is not what you are looking for, but I'm doing it like this becasue cloned DB might stay there forever. FlexClone is not good gor that if there are lot's of changes into the DB datavolume where FlexClone has done.
Only thing you could do if the cloned DB stays there for a long time.
1. volume copy or mirror the flex the volumename you prefer (do not use split)
2. You still need to shut down the database to umount and mount the new volumes.
3.You have now your datadirectory where it should be.
4. detach (NOT REMOVE OR DESTROY) your metadata from smo (now the snapshot can be deleted where clone has been taken..