It depends on a number of factors.
Most important of these, if our opponent in the semis has their NRL side playing an NRL semi in NSW, it is unlikely. Shame because a stand alone home semi at Henson Park would mean loads more publicity for RL than if it were a mere curtain raiser to the NRL.
E.g. At this stage, Newtown is 2nd and the Cougars are 7th. If Penrith had an NRL semi final in NSW, it is likely that the NRL (or the Panthers) would ask that the PL semi with their club be played as a curtain raiser, despite the fact that they have enough resources to play the match somewhere else and the fact that we deserve some reward for finishing 2nd.
As for the number of contracted oplayers in the Newtown PL team, it was always the agreement that this would be gradually phased in. Next year and as the years go on, there will be more Newtown contracted players.