The fact is that there are just too many imaginable ways that such a video artifact could be released, even by well-meaning officials, and still be fake: As the OP article states, the secrecy in government agencies creates many perverse, confusing incentives that can have unintended consequences.... and we never have enough of "provenance" of any artifact to be able determine its veracity.
For instance, how do we know that the military doesn't have a secret computer graphics team that was tasked with making a demo video of what a UFO may look like, based on eyewitness testimony? Then, the infamous Navy videos accidentally leaks, but the CG team is super-secret, so officials have to pretend they are real, to protect the secrecy of their CG team? (I'm not saying that's what happened, I'm saying this is one of 1000 possible mundane explanations for these videos)
In summary, I don't think the CIA/military are technically capable of providing incontrovertible evidence for anything, they are simply not built to be trustworthy on these kinds of matters. This is because the scientific method requires open access to their data gathering process, which goes against their obsession with secrecy.