I don't understand your point. You seem to believe he should provide evidence that can be used against him in his radio show so that he can claim the 5th during trial. That makes no sense to me.
I don't expect him to incriminate himself on this show. I don't hold that against him. I am disappointed in his conduct and any money he (allegedly) may have contributed to the illegal drug trade, albeit prescription. Nonetheless, as long as he does not lie publicy, I'm content for him to remain silent and take care of his problem. Law enforcement and prosecutors will determine if there is a need to charge him. It's not like he is a violent perp. He has only damaged himself and betrayed the trust others had in him. He is still an articulate spokesman for what millions believe, albeit his role will undoubtably be diminished or changed.
I agree with you. I am disappointed in him, but legally he does have to protect himself. Sadly, he put himself in this position.
But his concern should not be coming back to the program in 30 days. It's an arbitrary deadline, one he may or may not make--even if he comes out of rehab in 30 days, he may be fragile, both physically and emotionally. The pressure on him to come back within that time period has to be enormous (both on himself, his radio show, the stations that carry his radio show, the advertisers on his radio show, etc.), but that should not be his focus. His career should be secondary to his health at this time. If he doesn't do it that way, there's a good chance of relapse.