I don't have video savvy so I won't comment upon whether It is genuine. Who took the footage?
I know Ed Grimsley, who helped popularize (or simply popularized) Skywatching with night vision googles. He got us to buy a pair or two and it's fun to use them to see the night sky or look out at the landscape. I don't agree with a lot of Ed's conclusions, but I think he is honest about seeing what he sees - I hope that makes sense. There is some intriguing stuff up there that goes beyond satellites, space junk, or birds.
I have seen something triangular and what Ed would call a formation with lights that come together and change directions. When using night vision, it is easy to differentiate between flocks of birds, insects, and other natural phenomenon. Planes and some satellites can be recognized. But I would not put a label on anything that goes beyond that. There is a lot of stuff up there. And there could be a lot of sources for that stuff.
So I would not hazard a guess about the first video - whether it is genuine footage or what it shows. Assuming it's genuine, I don't think it's birds. Or it does not look like the flocks I have seen. But that is as far as I would say based upon a video that does not provide a whole lot of context.
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