The wing bolt plate is on the other side of the wings, under the belly pan. It's there.

Having the space between the mounting holes lets the wing secure to the sides of the fuse, and not to a point in the center of the plane. This would give it a little more stability and ensure there is no gap between the plane and the wings.

Maybe you could try a new set of bolts? Maybe they got stretched or stripped? It shouldn't take much force to screw them down, and as soon as you start to feel resistance, stop.

Also, maybe check some other planes and compare the wiggle room? Just an idea, but I know my Yak has a little 'play' as do the SebArt planes at my field (I asked the same question with respect to my Yak).

Just thinking out loud, but like I said I don't remember anything out of the ordinary with that plane. I was shown to carry it to the flight line by grabbing a spot on the wings and feel that I really would have noticed something if it wasn't right. If you want to post a video I'll take a look at it.