I think the umpire knew he had no prior DS, he penalised him for insufficient effort to get rid of the ball. How a player who has one arm pinned and is on the ground can demonstrate sufficient effort is beyond me. Degoey was clearly trying to extricate his arm so he could handball.Yep, that was a bad decision. No idea how DeGoey had prior opportunity there. The player who actually goes for the ball, rather than going for the tackle, should have some leeway, which is why the prior opportunity rule exists. That was a silly decision, the commentators effectively said it was silly, but their solution for a player in DeGoey's situation was pathetic.
DS
Holding the ball, prior opportunity, insufficient effort to dispose of the ball …it is a mess and a lottery