Oh wow, so before Malin was even cast for Season 2, she was an extra in Chris's intro video for Season 1 (the ones where they like film staged interactions - his was him on a plane eyeing up Malin as she walked past) and they both knew each other from 2 years before Love Island when they were on Take Me Out together. And after Malin finished filming for Chris's intro vid, she messaged him telling him who some of the other cast members were gonna be because she was filming for those ones too
So before he went in he already knew that Luis and the Italian twins were gonna be on the cast, so he was able to look them up on their socials etc and see who they were