Is the binding bias or straight cut?
If you bias cut the binding you'll have an easier time with the fold on the inside corner and you won't have to clip them like you did.
Also, it looks like you machine stitched the front of the binding, I'm "guessing" you attempted to fold the binding and stitch both front and back at the same time?? Correct me if I'm wrong. But I think this is why you are getting the ripples because you are trying to hold both sides of the binding taught and sew at the same time - and stretching the quilt in the process.
At a minimum you are going to have rip the binding off and make a new one, preferably a bias cut binding so you can turn those inside corners.
Once you have the binding off take a look at the quilt to see if those edges are still rippled. If they are, you should probably block it to get it to lay straight again. I'll be honest, blocking something that shape isn't a chore I relish
When you attach the new binding, sew it to the front first by machine, then fold it over to the back and by hand, whip stitch it to the back. I think with the number of corners you have this will be the easiest and most accurate method to bind.