Can someone explain why you'd use the 235 isotope? I know there are different magnetic properties but it still seems an odd choice to use something that is highly controlled, difficult to produce, and rather dangerous. It seems like there would be far better choices unless you absolutely need that mass or they very weak valance electrons.

And those videos being identical is also suspicious. [2] Uploaded 2 days ago, claims 235U substrate, is from @q-center, and created their youtube account in 2012. [3] is from @qcentre, uploaded 5 months ago, claims Cu substrate, and created their account in February. If it was the newer account posting the new video it would be easy to believe lost password or something but this reversing feels weird. It makes it feel like they changed the video description (but didn't edit the original to prevent history checking? But could have just uploaded a different video?) to combat the induced magnetic field as claim?

But it feels like it gets even worse. [3] (older) is a 4k video while [2] is 720p. Just hiding detail? The material looks neither like copper nor uranium ceramic (very distinctive orange color), but that can just be the material which is claimed to be thin film deposited and that's believable. Maybe they're hiding the sample identification etching on the front? I'm not sure what those mean and it's very possibly arbitrary. But adds a level of suspicion.