Dynamic account permissions and/or multisig could solve this? I mean, if it's a "small" BitAsset maybe, but if something like a huge company decides to do so..
The only thing that I see can be used as insurance for extreme situations like this is a prediction market
Also, for someone to use someone's private assets, it's because it needs to be an entity you trust. Ok, nothing prevents them from doing so, but by being a well known company/person, can't those be made responsible? For their assets to be used people need to be confident enough, have enough information on the entity providing that service.