What makes you think that? There's literally no buzz surrounding him. None. His performance in the combine has basically been invisible. He hasn't sucked, but he hasn't impressed. None of the draft experts and gurus have him getting drafted except for one. I just can't understand this line of thinking.
I think your last sentence carries a ton of weight though. Ultimately, if he thinks it's NBA or bust, his decision should be based around what is best for his development. The problem is, he'd be giving up roughly (allegedly) $2.5M, and that's assuming he could actually get a two-way deal. To me, that's an insanely bad decision for him to make. Here's a hot take, he won't make $3M his entire NBA career. Take the bag and chase the dream next year.