Looks like partial starvation. It takes a long time (minutes to hours) to turn a crank black like that. Whether you had an oil passage plugged or not, the engine failure was probably oil related. The way it looks you probably experienced a power loss of getting slowly worse before it failed, and possibly burnt oil smell, but not always.
There can be a few things leading to this:
Wrong oil type.
Plugged oil passages.
Debris introduced during an oil change.
Use of excessive silicone when servicing engine parts.
Extended service intervals.
By the looks of that connecting rod end, it was extremely hot before it failed.
When engines are used in performance applications, service intervals will drop significantly. Service intervals are recommended based on driving conditions. 5,000 miles would be typical driving. Severe service is 3,000. High performance operation is less than severe service.
Now I'm not saying you abuse your car, but to a warranty company you have these strikes:
Broken engine mount - Indicates customer abuse.
Exhaust cutouts - Indicates you race the vehicle, which in the contract voids all responsibility to the warranty company.
Typically warranty companies do not care about mufflers.
Other things that will void specific parts of your warranty.
Oversized wheels and tires WILL void any warranty pertaining to your suspension. Since an adjuster inspected your car, suspension warranty was probably voided. I have seen this many times on Super duty trucks.
All that said, I don't know if they have substantial grounds to decline your engine repair. But do remember you signed the paper that described what is and is not covered, you should find that and see if any of your habits are under the not covered category.
Good luck.
-Pat
