I was disappointed with the Dave answer too, the same "he's busy with his own production company" -
Well frankly what good would it do to say (if it's true) we hate each other other than giving the tabloids fodder for more negative stories?
I just thought it may have been a great opportunity to put a firm closure on things if "something" has happened between them, for the fans that are genuinely interested in hearing Dave work with Chris on the radio again, rather than hover over the subject with the "Dave's busy" angle - he could have simply said, I didn't ask him back, we no longer speak, something down that line, he wouldn't have had to go into full details, he mentioned that during the interview that there are some things that he like's to keep private.
He did a long periscope video the other night and a huge number of the questions being asked were Where's Dave, which he tried his very best to ignore every single one... until he mentioned it generically about everyone else in his old R1 team.
They had a great thing going on together for many many years, for him to just vanish with little to know mention, then of course it's going to getting people asking the same questions until they no a little more or hear him on the show