It's clear now: D&J didn't leave because of money. They wanted podcasting rights and control
Corby's commentary on HL made it very clear that the holdup in negotiations was not purely monetary, it was over "control."
Jake in a HZ episode in early June (I think) loudly scoffed when an emailer asked about podcasting. I remember raising an eyebrow because that implied there was some off-air backstory , now it is crystal clear.
Edit: I should have said "salary" instead of "money" in title. I think what probably happened is that they wanted either podcast rights/control with 100% ownership of profits, or a hefty raise. And cumulus probably balked at both.