This is the set you can buy online. The flue vent is clearly to the right of the top cover. My vents though look identical whilst the ones in the video clearly are different. I guess the idea is that you dont cover that top bit where the flue is on the top vent on the right in case you are going to use it in winter on gas I suppose. I think I could probably buy that set and just put the top one either to the left if I am going to use the fridge on gas in winter (doubtful but not out of the question) or in storage or on hookup I might be able to slide it along to the right to cover the flue.
Dunno. I might just follow uncle Tims idea and just say bollox to it.
My vents