Servers cache the original values of modified sections of rogue servers Authentication Trees. The combination of protocols in clients and servers ensures that users can choose which filters they want to subscribe to. Companies may be satisfied with the subset of names that survive the policies of a monopoly unaudited root server. People who want more robust names can use the root namespace explicitly. For efficiency you probably want namespace servers to do the auditing.
Users can of course independently audit also.
The system proposed is vulnerable to Denial of Service. There is no barrier to hostile users creating names as fast as their network connections allow. A robust solution would be payer anonymous ecash, but then we have boot strap problems, as there isn't one yet, and global e-cash systems robust against being themselves censored are probably an even harder problem. Perhaps you could use hashcash to throttle name creation floods. Name creations are infrequent enough that users could put up with a reasonably expensive computation.