You might:

Ask the factory to weld a pair of strikers each to an approx. 3" long metal bracket with holes and paint.  Or you could have this done locally in a manner so these plates clear the existing misc. screws which hold things together.  These new holes will get you virgin material for sure and provide a stronger anchor than the original.

Have your local dealer or someone capable to reinstall and adjust the latches for the added material thickness.