RE: OS 91 problems
From your pictures, your engine wasn't "fried", but had some kind of foreign object run through it. The plug could have dropped an element, a bearing could have had a partial failure, something could have been sucked into the engine, and so on. Only a full rebuild will fix the problem. If it's sent to the service center, we can check to see if something in the engine caused it, but if the cause was external, the warranty wouldn't apply.