It doesn't sound like it qualifies under either criterion. Local festivals don't count unless the "local" festival also happens to be a major/widely recognized one; and neither do non-professionally reviewed videos.

[BTW, I tried posting this reply using my usual Firefox browser, but the reply button was nonfunctional, so I had to post it in Chrome browser.]

It's extremely unlikely that the music videos qualify. Very few music videos do.

What is an extended music video? Music videos are generally as long as the song, or longer when they add some scenes before and after the main part of the song, is that what is meant by this rule?

The only exception that I can think of, and a good example of this, is Thriller: https://www.themoviedb.org/movie/92060-michael-jackson-s-thriller

And what does it mean that a music video is "screened as a movie"? Can music videos be screened any other way?

A music video can be and almost always is screened as a music video. Some film festivals have non-film categories (eg. music videos, ads, art installations). Others have extremely lax Shorts guidelines that include various types of video content. Most film festivals are not making any kind of statement, they're just inclusive.

In my understanding, it means that major film festivals have to screen a music video in their short film-only category. If the top festivals make a rare exception for it because they consider it to be "a movie," then we most likely would too. But honestly @lineker knows this stuff a lot better that I do.

Considering your posts it seems correct not to add them. Thank you for the explanations.