I Am Asking On Behalf Of My 34 Year Old

I am asking on behalf of my 34 year old son. He moved to another state approximately one year ago with his then boyfriend. Months after the move he and his partner developed a full body (minus soles of feet ,hands and face ) bumpy itchy blistery rash. Itches much more at night. My son has been treated with creams and antibiotic twice for a dx of follilulitis with no relief. Rash is worsening. My feeling is that it is possibly scabies but doctors are not treating him for this. Any opinions on this. Thank you