EV Vault Cache settings to prevent Synch of Ingested PSTs

Hi

If a user has Vault Cache with a 10GB size limit enabled and then ingests a 30GB PST is there a way to 'exclude' these files from filling up their Vault Cache space?

I can't see any way of doing this but just wanted to check..... If the PSTs were ingested with a top level folder called 'Migrated PSTs' which was common across all users I still don't think there is a way to exclude folder names from Vault Cache synch.

Ideally I'm looking for a solution whereby the users must use 'search' to access their PST's (rather than using shortcuts in their Inbox' but equally want the Vault cache users to have the full content of their archive synchronised excluding their Ingested PST content.

thanks