A few laser welds on each side of the clasp builds up the area missing steel to the original height without needing to make exaggerated bends on the tabs or deforming the clasp cover in the process. It's also a repair that will be good for many years.
Now the backside of the extension nests fine. The center still droops. For this we will need to replace the rivet.
We use a cutoff wheel and a punch to remove the old rivet. Lol, sorry rivet off with your head!
One new Rolex rivet pin