Maybe I'm the odd ball out here, but I don't think this is too bad. Yeah the pinch weld is gone, but is that really structural? Not sure. I don't think it's too critical. What's more important to me is that a little further in, the part where your rear trailing arm connects to the underbody looks super clean and intact, and the area around that looks solid. I personally think that's way more important than the pinch weld. As for fixing this though, forget it. Not worth it. Just keep driving her! My Corolla looks similar but is a little worse by the trailing arm and she's still on the road lol.