Does he make the roster? No. If there's anything we've learned over the past 5 years it's that the center position is changing drastically, and the game is demanding more from bigs in order to secure a spot in this league. The prototypes are typically a rim-running defensive specialist (e.g., Capela, DeAndre Jordan), floor-spacing shot blocker (e.g., Lopez, Gasol), or all-around freakish All-Star (e.g., Embiid, Davis, Cousins). Tacko can block shots, sure, but he has no jumper, can't get up and down the floor well enough to score in transition, and has suboptimal athleticism (i.e., lateral quickness) to allow him to defend the pick-and-roll and isolation scorers.
I'd love to see it work but there's a reason he went undrafted. Here's hoping I'm wrong for our sake.