"I'll double check on Monday... but, I remember seeing a sign in DUB that Quantas cards, for whatever reason, couldn't get you in to the Gold Circle lounges. Something about the agreement between the two airlines being suspended. I'll get back to you on this."

That could be related to Qantas Club members ( paid lounge membership ) rather than to Qantas Gold/Platinum members. I would be surprised if there is any issue with access with OW status
Dave