Is his H-1B cap exempt?
-I think so. From his description, his friend just found a tenure track posiiton at a school, so most likley his friend's current job should be at a non-profit reseacrh institute or a at school. If his current job is in a industry company, normally it is difficult for him to find a tenure track position because employees in a compnay normally do not publish research papers (or publish very few), but apply for patents. Thus, it is difficult for them to find a tenure track job if they do not have enough or high quality papers.
Otherwise, if selected and approved, his starting date will be on Oct 1. The employer wants to keep him until June 1.