Fixing topper latch

So I've had this problem for a whole and I'm wondering if anyone else may have dealt with something similar. Basically one of the latches on my leer topper won't latch. It looks like the metal arm that latches behind the catch plate isn't long enough. I'm guessing that the topper may have "spread out" at the bottom over the years. The latch on the other side works fine. Any suggestions on how to fix this? Perhaps a way to make the arm longer or extend the catch plate? Here are some pictures of what I'm dealing with.

 

Undo the clamp in that back corner, then have a buddy (or try to do it yourself) push the corner of the topper in while you reclamp it in place.

 

This didn't really fix the problem. I'm gonna try again tomorrow when it stops raining. So frustrating.

 

slide the glass over

 

What does the other side look like ? Are the margins the same ?

 

The other side sits flush, looks like it should.

 

Any chance the bedsides have spread ? My old Ranger had that happen from a lumber rack , actually ended up spliting the bed

 

I'm actually thinking a slightly bowed out tailgate might be the problem, I'll post some pics in the AM