the bottom line at the end of the day is.. you boosted your car.. your engine go bye bye. buy a faster car next time.
in my opinion, AA came on here and made a bolder statement than you. That thread created by a representative from them, obviously with the whole company's approval, put their entire company and brand at risk. I highly doubt a established company like AA or any vendor on here, that wants to do business and realize that forums are 99% of the customers, would disclose this kind of information. Meanwhile your story is shaky on top of everything else. A business wouldn't have risked their name if what they were posting wasn't true. If something was wrong with the way the kit was designed/tune etc, dont you think an issue would have arose sooner?