I think it's safe to say that there is probably more than one adjunct who is doing sex work (somewhat based on my experience of having read this type of story before in the past years). But I agree that the headline and framing of this story deserves scrutiny. I don't think it's coincidence the way that the first sentence in your excerpt ("Sex work is one...") is immediately followed by a sentence that alludes to a statistic ("A quarter of part-time college academics") that ends up being unrelated. The close juxtaposition of the sentences could easily be misinterpreted as "25% of adjuncts are doing sex work").