Lots can happen between now and closing arguments. He's getting a lot of money raised for a defense team. You know, that whole pesky "due process" and "innocent until proven guilty" stuff that you may have heard of?
I will say that he had no legal right to carry, open or concealed, being 18 - that's the law (sorry, not certain if that's Kenosha law or Wisconsin).
Also, why can't they prosecute his parents? That will probably be next, either criminal prosecution of them or civil suits.