Did Ramon Merceder Really Become Cuba's "Inspector of Prisons"

Somehow I am dubious:

http://books.google.com/books?id=GtGbCSaH51EC&pg=PA147&lpg=PA147&dq=Ramon+Mercader+fidel+castro&source=bl&ots=kAdTE8rV9s&sig=wdJHATh41gVmNqvzF5wOKia2-0Q&hl=en&ei=UUxzTNyCHITAsAPq2OTPDQ&sa=X&oi=book_result&ct=result&resnum=42&ved=0CPYBEOgBMCk#v=onepage&q&f=false