That looks like appropriate sized prey. If anything maybe little small based on how fast it was ingested, though the video doesn't show the whole process. My general approach on prey size is this, if the snake can ingest the entire meal from the time it actually starts in less than 5 minutes, I increase size. If it takes more than 15 minutes, I decrease size.
I thought the same thing but Im pretty sure the video was not running at true speed and seemed to be running a bit faster.
KMG
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