Update: I disputed the claim.
I looked at what portion of the video was copyrighted and found it to be a siren sound. Again. This is the second time a siren head gameplay on my channel has been copyright claimed because of a siren. Last time it was a song that used a siren.
If this happens to anyone making a gameplay on this or any other siren head game, check what portion of the video is copyrighted, and most likely it will be a siren which is a real-life sound created by tornado, air raid, or other emergency sirens. Just dispute it with public domain and explain what a siren is.
Amazing game! I especially love seeing something made by Unreal Engine, as it is awesome.