When Karina is introduced, she speaks to Des while he's talking to Darby and Victoria. But she then attempts to rudely dismiss them, "mistaking" them for customers who wandered in, saying this area isn't open to customers, when it's clear they're with Des, someone authorized to be here. If they were truly interlopers, he's already dealing with them, would know for certain what they were doing here, and would tell them himself.