Uh.... exit interviews. Even if you found that your org was so f-ed up they didn't do them, as part of your 'pulse' the first four coffee's should have been a 10 minute meeting at the nearest coffeeshop to the four that left you.

If you asked politely I bet several would agree.

We really still don't know what is going on.

you dig to uncover truth was a good idea, but not enough to really know.