Rugby union players are a slightly different matter. Most union players, particularly backs, are more dexterous than their league counterparts, basically because there's more kicking in union than there is in league I guess. And, there are certain individuals who are simply freakish with sporting skill. The Canadian guy that you quote may be one of them.
I know from my times playing both codes. Most league players were hopeless kickers, and most union players were much more adept at the skill.
Go through the lineup of NRL teams and see how many players there are that you think could make a successful transition to Aussie Rules, such that they would be regular first graders with AFL clubs. Very, very few indeed.