Interviews, afaik, don’t hold much sway in admissions decisions. It’s hard to believe a college interviewer told him that he was being compared to another student with more experience. That’s just weird and probably unethical.
I also don’t know why he wouldn’t mention his experience. There are probably millions of people in the world who have gained experience and started careers by working alongside parents, ore getting a job due to parental connections. We all know this happens. Why not just talk about his experience? He doesn’t have to preface anything with “My parents got me the opportunity to research/got me the job/it was at my parents’ work…”