Ok I just read that post and it has nothing to do with the Catleap monitor. It has to do with a completely different set up. So I am now not believing it has anything to do with the boards we are trying to source.
Here is the monitor it is in reference to: CLICKY
I don't buy these are the same thing since ours are tuned from the factory at 60hz and not rated at 120hz. Furthermore, we could never get 120hz out of these things.
I found the monitor will display a usable picture at a lower resolution as long as the horizontal resolution stays at 2560, although part of the next frame is shown at the bottom of the screen. Doing that, I was able to get 2560x1000 @ 122 Hz. I could not get 125 Hz at any resolution, so it seems like the timing controller was actually designed to handle 120 Hz and not much more.