Disguise themselves! There is something to that, although if the damaging is being done... in their own homes... then he suspects the disguise may be worthwhile.

"An intriguing idea," he allows, "I'm not certain if we will be allowing one into our home. If you do find the time to take one apart, I'd be interested to hear your results."

You can be the guinea pig, in other words, and do tell him what happens if you attempt this.