P.H.
Just a thought, but maybe take the cushions off of the chair so it's not comfortable and tell him they are lost or being cleaned.
Or a more drastic approach would be to lay the chair on it's side and tell him it's broke.
If he still cant sleep good in his bed, I know that the bassinet/play yard has a vibrating device on it to sooth newborns maybe some thing like this would work on a crib or headboard.