I had a similar experience. I had just completed a brood inspection, where I found a nice, fat marked queen, and, out of curiosity, I had a quick look in the supers only to find half a frame of sealed worker brood on the middle frame above the queen excluder. In conversation with a local ex bee inspector, he reckoned that when queens were short of laying space the workers would sometimes move eggs around.
I have heard that before from the chap that chats about lay lines, sorry cannot remember his name right now.
I remember reading in the comments of the you tube video and weather it was possible seemed to split opinion. No one had gold standard evidence it can happen.
I cannot say I am convinced bees will carry eggs, but I would not write it off as impossible either.
I just got back from removing the QE, I had a peep in the top brood and sure enough there is larvae below the QE too! There was also some brood in at least one of the other supers too.
I have only seen this queen a few times, she is quite small compared to my other queens, she looks kind of long and thin. I wonder if she can squeezes through the QE.
This hive swarmed early last year, and was re-headed by the current queen. Last year I put one super on this hive and had exactly the same problem with brood in the super and removed the QE.
I only remembered this after looking at my records last night. If I had remembered this a few days back I would have been more open to the suggestion of there being brood in the super.
I will also check the QE for damage when I bring it in tmr.
I am leaning towards queen squeezing though the QE for me this time, as the same queen pulled of this trick last year. But yours may have been carrying eggs. And mine may have been carrying eggs two years in a row!
Recent events have taught me to stay open to all possibility until you know for sure.