Nathan Brown is trying to turn around the culture of newcastle. Some of that is getting rid of overpaid and underperforming players. They've already moved on Uate, Tariq Sims and rochow, mullen (even before the steroids) and korbin were rumoured to be on thin ice.
Sims moving on would be good for the Knights, they no longer have a player who's causing trouble around the place with a bad attitude. Getting rid of korbin may open the door for todd carney and/or getting Ponga a year early. There's plenty of upside for Knights in letting him go, even with pauli pauli's injury.
I think the biggest thing holding up sims release is price. Knights don't want to be paying any part of his contract to play for another club. Broncos are trying to sign sims on an Andrew Gee special deal. Souths are offering close to full amount if the runours are to be believed. Broncos looked to have cap spaced cleared with roberts troubles, but it looks like he maybe not getting sacked after all.
So its all up in the air