If we want to have the right to search and find out who our birthparents are, we have to be ready for not-so-pleasant surprises. Knowledge hurts sometimes. But I believe secrets can hurt more than knowledge, and most of the time knowing is better than not.
It sounds like Roberts did not have support--an adoptee group or therapist trained in adoption issues--when he began the search. Searching can be such a lonely, terrifying experience (let alone if something like that happens!) Reach out, all you searching adopteds. Reach out.