I am more and more inclined to believe price isn't the most important factor in DVD's decision to exercise ROFR. I think they are mainly looking for particular "units". It's to their advantage to have larger chunks of points with the same "unit", so that they can offer larger contracts.
AFAIK, even DVD cannot mix points from different "units" in the same contract because points represent a percentage of a particular "unit". There's no way for us to know what "units" they have in inventory and which "units" they may be looking for.
OP - Just keep trying, and don't over pay on the next one. Here's hoping you find an even better deal. Good luck!