I think he means buyout for opt-out. He is a very good player in euroleague, so why would a club sign him a contract such that he can walk freely just after one year?
These European contracts always work on the "buy-out" system. The Euro teams always want something in return if they lose guys. They aren't going to give anybody a true opt-out in the sense that the player can leave for nothing. After next season, the rockets + span can pay off the 400K, then he's free to play in the NBA. That's how 99% of these Euro contracts work.
Didn't they impose a cap on what the NBA buyout clause for a European player would be? Anyone know the figure? I'll assume 400k, since that's what VS's clause is stated at.