I think it is more likely that Missling learned a lesson with the bogus class action suit filed against the company. That cost the company time and scarce resources and also made it clear that the shorts would use any dirty trick or opportunity to damage the share price.
Since then Missling has walked the very straight and narrow so to not provide another opportunity for those sorts of shenanigans.
He probably could provide more information than he does without much risk. But given the potential harm and the large short position, playing it very safe is a good plan. After all, it is the trial results that will decide the fate of the company, not well received conference calls.