I think he may have had a clause in contract to say he could go if approached By a SL club. I think it was Wakey rather than him who were doing a dirty on Fax by saying they were a Super league club when they actually signed him though they were in Championship when he was approached.
It depends how the club see it and if Walmsley had any blame whether he would be welcomed back.
He still scares me silly when defending though.
I may have got this totally wrong though.