Fans of Ex On The Beach will remember that Gaz initially denied cheating on ex-girlfriend Lillie Lexie Gregg when she quizzed him about it. Lillie grew suspicious when Gaz said an ex from Australia, Chrysten, had surprised him on the beach, and he couldn't remember the exact dates of when they hooked up.
To the camera, Gaz admitted he had cheated, but to Lillie he insisted he hadn't...
We caught up with Rogan, who is friends with both Gaz and Lillie, and he told us that he "knew something big" would happen between the exes on the show.
Speaking at the launch party of multi-vitamin supplement HangDr, Rogan said: "As soon as Gaz was going back in, I knew something big was coming... I could see it happening."
Although, he wasn't so sure that lying about being unfaithful was Gaz's best move. Rogan added: "I mean it's on TV, he should know by now. He's been doing this for about five years, he should know."
Adding that he can understand why Gaz had backed out of telling Lillie, Rogan said: "He obviously still cares for her and didn't want to upset her."
Lillie did eventually find out the truth, when Chrysten revealed she had slept with Gaz while he had been dating Lillie. She broke down in tears and branded Gary a "horrible person."
Like Gaz, Rogan has been on Ex On The Beach twice before.
He actually starred alongside the Geordie Shore star in series two, before returning to the show for series three with Vicky Pattison, Kirk Norcross, Cami Li and Jordan Davies.
Rogan had been a fan favourite to return for Ex On The Beach's all star series, but currently being loved-up with girlfriend Chloe Francis, he has given it a miss. That doesn't mean he doesn't think MTV wanted him to sign up, though.
Pointing out to us that a slew of his exes are on the show's fifth series, Rogan joked: "I think they did they want me back in, if I'm completely honest with you. There's about eight girls in total and I think six of them are my exes."
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