I would contact the RPRA offices and explain to them what you have expressed here on the site. As already been said the owner of this bird has a responsibility to arrange to have this bird collected from your dads home and the fact that a non-fancier is involved the period to have this problem sorted is much shorter (7days). It doesn't matter if the bird is AWOL since 2011 which to me just sounds like a cop-out the owner must act and have this bird collected