The Warriors confirmed on Friday that Walsh is now in isolation and will return to training when the team reassembles in Redcliffe following next week’s bye.
Storm coach Craig Bellamy is confident Cameron Munster will be available for Origin III while the Knights will be without Kalyn Ponga for their clash against the Titans on Friday night.
Munster was ruled out of Thursday night's clash against Manly with a shoulder injury suffered in Origin II with Bellamy indicating post-match that his five-eighth will rest his irritated AC joint but be available for selection in the decider.
"He wasn't far off playing tonight," Bellamy said.
"I think Tuesday at one stage he was playing and then he wasn't. I think he'll be fine for Origin, as far as I know."
Storm and Maroons teammate Felise Kaufusi also missed the game against Manly for family reasons, having flown to America to be with his father, who has been admitted to hospital.