[OrgNet]

Maybe describe how big the attack was in a communication with the customer? ie: how many connections per second, bandwidth used, etc? If you could trace the attacker and prosecute them, that you be a lot better, of course (and possibly the way that would gain the most confidence). In other words, if any of your claims could be confirmed by a third party, it would be good. Or you could propose to them to be hit by the attack for a set amount of time before you move in.