On the surface, and despite the fact that I am not a fan of Djou, I will say that there may be merit to the complaint. However, in the world of politics, I also have these observations:
1. It would seem that the CB poll showing Djou down by 7 may have something to do with the timing on this. 
2. That, with that poll, whether accurate or not, it is showing Djou that the prior attacks on Caldwell regarding his "salary" at TSB is not having the desired effect. The issue is muddled by the fact that while it may seem by perception the salary is unethical, by the law it is perfectly legal and has been upheld. So voters are conflicted by either thinking it is wrong by perception, or right by law. Because you know perception and law sometimes don't line up nicely. 
3. In all honesty, this information has been out there for a while. So if this was such a big deal, Djou could have filed the complaint way sooner and leveraged the inaction by the now-Totto-less board on a message directly to KC.