Here's the thing: For us as fans and maybe for PATFO, what Nikola is doing is training. For him, it's a job. Olympiacos offered to pay him the most money, so that's why he's there. The Spurs didn't assign him to a place where he wouldn't get minutes. He played a lot for Partizan, but they couldn't pay him (literally -- he had to file a grievance over the issue just like Bertans did). The Greek team was going to let him out of his deal to sign with a team in Serbia, but that didn't work out.
The solution would be to bring him over and let him play in Austin while being paid the most as a Spurs prospect. And I'd rather have him on the team than Forbes right now. But once he wasn't going to be a Spur for this season, it was all Milutinov's choice to do what's best for him and his future, and current finances are a big part of that.