I thought Desiree (short hair) was the blonde QVC model who is now one of the IT Cosmetics reps. Jaime (long hair) is the blonde QVC model, who is still a model as far as I know.
But more importantly, why assume because we have only seen a person as a model that they don't have qualifications for anything else? Would IT Cosmetics really hire someone who was lousy at the job and risk their sales? Like anything else, I'm pretty sure they had to show qualifications, go through a training period, and be selected. I guess they also get a boost because the viewers have seen them wear the makeup already and "trust" that it works as they've seen before.
Some of the QVC models are also actresses, some are nurses. I would never presume any limitatons on anyone.