D league will help determine if he is developing. From what he did in Australia, he has a lot of that to do. He was on a losing team but it was rare that he showed glimpses of someone who could survive in the NBA, let alone contribute on a contending team.
Different country, different way of doing things and basketball, though it has a pro league, is a minor sport. Maybe he can shine in the D league or do enough to make him attractive to someone. He is worth giving time even if he is never a NBA player.
I would be happy to be proved wrong but I doubt he inspires many more threads.