There is also another theory that Magnus had a leaker in his prep group, and so prepped an obscure line that he doesn’t play (hence g3) to see it the leaker would leak his prep, and after Hans knew what he was doing - Magnus left in anger due to the leaker. Regardless, we won’t know until he gives a reason.
Oh , yeah this makes sense. Its quite hard to find out who it is
Maybe someone from STL helped Hans? He's American and STL is an American cup,