You are obviously not old enough to remember, or you have selective dementia, because it happened in 2017 to another Manly fullback, Tom Turbo, and it was against your mob. The injury put Turbo out of the match. There was much controversy about the ridiculous rule at the time because it means whenever a player is in the air - such as from a grubber kick or a ricochet - you can take out their legs.
Manly will get the usual "we're sorry, we got it wrong" apology from the NRL for the second match in a row, and will wait until a similar incident happens to one of the favoured clubs before it changes the rule.