This is clear to me. using the query option you can make sure snaphot delete operations will not require additional approval for volumes matching a pattern:
rule create -operation="volume snapshot delete" -query="-volume !CC_CVLT*"
with this rule deleting snapshots will trigger an approval request only for volumes not starting with this pattern. I would like to know if this can also be done with requested user but I have not found any detailed documentation for available options.