I don't think monetary damage is required, actually. Copyright also includes protection of the work as it is. Alterations are violations of the copyright.
For it to rise to the level of a violation, however, there must be distribution, and that's at the crux of this case and others. I believe in this case, the videos were rented out, which is a different thing.
If memory serves me correctly, and it usually does, there are cases of visual artists who have prevailed in cases where their art has been altered in some way by a gallery or museum that had purchased the artwork.
The courts have held that such alterations are a violation of copyright law and that the distribution is the public display of the artist's work.
Copyright law is very different from patent law. The intent in copyright law is to preserve the work of its author or artist from modification and duplication. Painting a fig leaf over a nude painting, then displaying that painting is a violation of copyright, since it is no longer the artist's work that is being displayed. Case law shows this to hold up.
A movie might well be treated in the same way...as a work of art, complete only if unmodified. Again, while the individual might escape notice, and might even rightfully alter the work, a third party cannot, especially if they are doing it for money.
I used to make my living as a writer for magazines. When I sold an article, it was under a contract that laid out my compensation and which rights had been purchased. The typical contract also allowed certain uses by other parties, but I would be compensated under the terms of my contract with the magazine publisher.
The publishers followed these terms, for the most part. However, on one occasion, I discovered that most of an article I had written appeared in a book by another author. I was not credited. It was pure plagiarism. I collected a tidy portion of the book's royalties. The funny thing was that the magazine publisher collected even more of the book's royalties, due to the revenue sharing terms of my contract with the magazine.
Copyright law is complex and very, very nit-picky.
Copyright infringement brings two kinds of damages. Actual (compensatory) of course applies if the author lost money due to the infringement. But an owner of a registered copyright can request, and the judge can grant, statutory damages of up to IIRC $150,000 even if he suffered no actual damages.