NHTSA Complaint #11629248 — 2018 RAM 1500

I have a 2018 Ram, with the 5.7 hemi. I purchased it new in November 2017. I currently have just over 53,000 miles and began to hear a ticking sound on startup that lessened upon driving but never completely gone and could smell exhaust fumes in the passenger compartment. I took this to an independent service center and they reported that two or the rear bolts have broken off that secure the exhaust manifold and the gasket has been damaged. The mechanic states that this is quite common but not a recalled area from the manufacturer. The repair will cost close to $1,000.00 to repair. I do not understand that if this is a common and well known and documented problem and can be a huge safety risk due to the leaking of carbon monoxide into the passenger compartment, why hasn't this t been listed as a safety recall. I now understand that RAM is also discontinuing the production of the 5.7 hemi engine, are these type problems related?