NHTSA Complaint #11618551 — 2013 DODGE DURANGO

My 2013 Durango with 124,000 miles has a check engine light on, that indicates cylinder 4 miss fire. The Airpark Dodge service department where I purchased the vehicle has done a diagnostic evaluation and determined that the left cylinder head needs replacing. That falls within the X56 engine left cylinder head extended warranty for some VIN # vehicles, but not mine. The estimated repair is over $5000.00. I am told that the engine can cease up while driving, and that I should not be driving the vehicle. I think my vehicle should be included, especially since this X56 warranty extension has been out since 2014. How do I get this X56 warranty on my vehicle? And how do I get reimbursed for the cost of the repair?