Sorry to hear about your RIR male, course right now it is spring and in the middle of breeding season. He would sure not stay long here either great choice for moving him on, you sure can not have that.
We have Large fowl RIR's that are wonderful birds, and know others that have birds from this line and the male and all his offspring so far have been some of the sweetest birds we have ever owned, he is great at the shows and lets anyone hold him. I think that is why some breeds are falling apart and get stereotyped they are being breed with all these poor traits to encourage egg production or meat which is great but I feel you can have both and like you do the right thing and not keep him or use him for breeding. Any breed of course can show some signs of aggression when it comes to being protective of hens or their young but being mean should not be tolerated.