Hm. That side panel looks a lot like mine, but it's hard to tell from the tiny photo. Mine was a translucent green, a slightly different but similar style to that case. It very well might be the same side panel style.
Did the tabs just snap super-easy, almost as if they were MEANT to snap? So easily, that the first words out of your mouth were "cheap taiwanese piece of sh
it"? Then it's probably the same one.
Try the RTV Silicone trick. Let the glue dry before putting the cover back on the PC of course.