[Plums]

Sorry to hear about the damage - that's just one of the reasons I don't like pets - glad to hear you're ok though. I agree with Mike, the owners are resonsible and you should seek restitution from them.

On to your power figures. I agree with Sonny, I don't believe that is a stock engine. A stocker will usually make around 180 - 190 rwkW's, with some up to 200 (it's very rare that you'll crack 200 unless it's been tuned before and the owner doesn't know about it). Getting over 250 at the wheels is also extremely rare, there are only couple of stockers that I know about that have achieved this.
It is possible that his Dyno was giving incorrect readings, due to the fact that it did fail during the session.