Just because you have the capability doesn't mean you have to constantly monitor it. The mere fact that you H would be willing to turn over that information should be comforting to you. If he does, you can just keep that access "just in case." If you ever get suspicious, you have the ability to check. If you check and find that passwords have been changed, then you know something is up.
There are books available on recovering from an A and they usually discuss transparency plans as well as other things your S should be willing to do if they are sincere about repairing the damage from the A.
Me: 48 y/o W: 47 y/o Together: > 20 yrs BD: Dec '15, then S 2nd BD: Mar '16, then I filed for D April '16: started piecing