Unfortunately, the video is not conclusive, even if enlarged. I have to vote with the bird group.
Despite the fuzziness of the picture, I don't see any arms with props, but several 'blobs' do appear to be extended wings.
No, there isn't.
What purpose do you imagine those things could have been following where you saw them?
What's bonkers is seeing a few birds, flying the way birds fly, in that environment and thinking ... those can't be birds, they must be some...
Without a speaker, I wouldn't have recovered my Mini 4
On it's first flight, I lost it in a tree and it couldn't be seen except from a very specific spot.
I could hear it which caused a bystander to look into the tree from that one spot.