Munster was back in Queensland's camp on the Gold Coast on Thursday and in good spirits, just 12 hours after missing virtually all of Origin II.

The 26-year-old's availability looms as the biggest talking point leading into the decider, with Maroons prop Christian Welch also expected back from a concussion.

Munster passed the off-field HIA check on Wednesday night, but was still prevented from returning after he fell taking a kick in his own in-goal in the second minute.

Bad balance is considered a category-one symptom of concussion, with Munster ruled to have displayed that when he fell twice as he tried to get to his feet.

The Maroons remain confident he will play next Wednesday, but it is not as simple as declaring him fit already.

Under NRL protocols, Munster must be assessed again before returning to contact training.

If it is determined he was concussed, he will only be able to begin with light aerobic exercise followed by some weights and running.

The earliest he would be able to return to proper contact would likely be Sunday or Monday, before getting final clearance to take his place at Suncorp Stadium.

"Players are rested and monitored for signs of deterioration," Queensland's doctor Matt Hislop tweeted.

"A repeat SCAT 5 is performed and if passed a graduated return to play is commenced.

"Prior to starting contact a player must pass an additional computer based cognigram test.

"The NRL have clear guidelines on safely returning a concussed player to sport.

"Thankfully most 'simple' concussions resolve completely within 7-10 days (in adults)."

Munster's status is sure to draw plenty of attention, after Boyd Cordner's exit from the Blues camp and the NRL's investigation into their HIA process.

Working in Munster's favour is that unlike Cordner, he has no serious history of head knocks.

Regardless, NSW will prepare as if they will face him.

The running five-eighth was desperately missed by Queensland in Game II, with the Blues targeting Ben Hunt in defence in their 34-10 triumph.

The Maroons also lacked his spark in attack, after he was one of their best in Adelaide.

"With the seven days you get the benefit, there is a time period around it," NSW coach Brad Fittler said Thursday.

"That whole left side of the field, they killed us in Adelaide off the back of him kicking and having a great left foot.

"When he went off, they lost that.

"They were shifting the ball there a lot but just weren't getting their kicks down there like they did in the first game. The whole game changed."

Meanwhile the man responsible for the contact that put Munster on the ground, Tyson Frizell, was on Thursday let off without charge.

There had been a question mark over whether Frizell had hit Munster while he was still in mid-air, however he was not penalised by referee Gerard Sutton.

Australian Associated Press