I thought a little bit and I think it is possible.
Peakmonster even done it at the start in that way:

Peakmonster (for example) take the escrow from the renter of the card and keep it.
When the contract (or day) finish normally Peakmonsters pay (for example every day) the escrow to the cardowner (95%).
When the cardowner has undelegated the card peakmonster sent the escrow back to the renter and the cardowner get nothing.