Any decent lawyer will tell you to shut the fuck up once you've filed a suit, so as I see it there are three possible scenarios here:
He's too stupid to listen to his lawyers.
His lawyers are too stupid to advise him to shut up.
They're trying a public pressure campaign against Mozilla to get Mozilla to capitulate before their case goes too far. They're hoping that the headlines of "Mozilla hates cancer patients!" will cause enough bad press that Mozilla will want to get the case over with quicker by settling sooner, especially if Teixiera doesn't have a very strong case.