Does the resemblance between these two videos tell us much?

A similar-looking shape is a starting point, not a conclusion. You would want to compare the original footage, camera angle, distance, lighting, and movement. If those details are missing or unclear, it is hard to tell whether the two clips show the same kind of thing.

I’d keep the claims modest. A resemblance can be interesting, but it does not establish what either object was, or whether the sightings are connected. First check what can be independently verified about each recording, then separate those facts from interpretations.