Mine aren't as bad as yours, but my right display is a little lower. I had to tilt it more forward to make it "appear" the same height.
P.S. How do you have yours both hooked up?
get some of those small, thin circular adhesive felt or rubber feet and put four of them on your "shorter" monitor...hopefully will even them up.
Is it an actual height difference, or is there an identical slight tilt to one side on both monitors? If both monitors had the same tilt, the side edges would be perfectly parallel, but there would be a height difference at the top and bottom where they meet.
Although this would involve spending more money, you can get a desktop mount and mount both displays up. Then you can height-adjust.
Just a thought. I just got 2 mounts for my displays and I'm pretty happy the way it's turned out.