The players definitely have leverage here. The combination of taking legal action and players looking to sign overseas is very unappealing to owners IMO.
If you had a star player as an owner how would you feel watching that player play for some other team...making someone else money and potentially getting injured.
I'm really hoping the owners come to their senses and get back to the bargaining table.
I really don't think the owners care about players playing in Europe (GM's, perhaps, but they are not involved in this). I think the owners look at it as free promotion for their brand (I have a feeling you will see a decent jump in Nets jersey sales in Turkey in the coming years), and the injury thing doesn't affect them much, because I believe they can void the players contracts if they get injured playing in another league (which is why players need to get huge insurance policies if they are playing overseas).
Now, the legal action has a chance to give the players a little leverage...as much of a chance as they can hope for. But I am not sure how much leverage it really is, since the owners do not believe they have any interest in seeing the lawsuits through (nor do they think the players can win the lawsuit if they do.
The only leverage this gives the players is that it takes Hunter out of the role as the person they will be bargaining with, and replaces him with Kessler and Boies. And, unlike Hunter, who could possibly save his job by saving the season, Kessler and Boies have absolutely no motivation to save the season. So, if they owners don't want to lose the season, they might need to sweeten the pot a little more than they would with Hunter in charge, to get an offer in front of the "union".