Neemi is a latecomer in basketball, I think he said he didn't even play it seriously until his teens. It's why he doesn't have a good feel of the flow of the game. It is a good sign that he feels more comfortable out there. I guess he'll stay in Stockton mostly for another year.
That's not totally fair though. He's guarding players that are basically PG's at the NBA level. That's just a bad matchup although yeah, Keegan isn't sticking on quick guards but he shouldn't be expected to either. They need to back off a little and give some space to react.