Nothing has been proven either way. Axaron posted a few rude/snarky posts and stated Dragonflight is the mobile game, which it obviously isn't, and left the thread.
Some took that at face value and think that proves anything he said up to that point is fake. Others think he was just being sarcastic or had gotten irritated after being called a liar repeatedly.
Either way nothing is proven and to say otherwise is just bias because you like/dislike the ideas he presented.
The new information from Frankystein seems to be supporting the previous Evoker class leaks.