Both of the students are CS majors. They presumably will both eventually work for similar companies. Why would the woman who is equally interested in computer science pass over the job posting, requiring an actual recruiter to be present, when the man does not? Do women get CS degrees and then leave to work in some other field post-graduation, not writing code? If so, that is a huge problem. Do they lose interest in computer science? Do they get sick of the male dominated environment in CS but just stick it out for their degree?
I would hope that the recruiter isn't, in fact, signalling something along the lines of, "your odds of getting hired at this company are greater than your equally talented male friend." If I were receiving that much extra recruiting attention because of my gender, that is the impression I would get.