my limited understanding is that there is no paperwork issue to play in Aus. He has a record, as do a lot of NRL players, but he does not need paperwork to play other than NRL.
He is elligible for GB, but not a UK citizen, so his southern hemisphere status is unchanged.
I think Mrs and wee one issues will be the big questions, sure he wont get picked for England again either, but thats no biggie is it, how wishing to rinse this again but his not being english prevets that.