I'm assuming we will get a statement from Bubba sometime in the next day or two regarding the whole thing. Also, I've read that there's an investigation going into how somebody got radio access. I've rented scanners at tracks before, but those only allow you to listen to the radio communication, not participate in it. There's nothing that actually lets you talk when you have a scanner. If somebody got onto the 23's radio, it shouldn't be that hard to figure out who had a radio that would give them access to the team's communications.
It seems completely plausible to me that Bubba was just shooting somebody a middle finger off camera, perhaps not even out of anger. Me and my friends flip each other off all the time, and the post-race interview I saw with him was very upbeat, happy, and joking around. I'm still not sure why we're pearl clutching about a middle finger overall.