I think Charlie may have used internet posts to build his questions.
When looking for the access to the show, I can across a site for the show that has posts for the interview.
The most recent post which was at the top right before the show was about the unfairness of the placebo arm in the study.
If I remember correctly the interview started
Hello people have been questioning if it is ethical to have people get placebo in the study.
Remember he has interviews on many subjects and many interviews a day so this may be how he finds out what people want to know.
Later he said as we know HQ has efficacy because it has been in the market for a long time - he provably meant safety because efficacy is what the current studies are trying to determine.
He does not seem to be a clinical study expert by any means.