If you block it, he won't be able to book it either. Has he submitted a booking request, or are you two in the inquiry stage? if he is just inquiring, you could always decide to let go of the verification requirement, then reinstate it later again.
Verification actually doesn't mean much, just gives us all a feeling of a little bit of security. Somewhere in the Airbnb explanations about verification it actually reads, " it's not an endorsement or guarantee of someone's identity"... so what good does it really do??