Hola Angel,
- As I know YouTube policy doesn't allows that anymore since 2018. Maybe there are hacks, but ... we cannot use them, it would be probably a violation of the rules. Or maybe now it request using YouTube Premium account and having YouTube API key. Please read more in Google Developer guide.
Our slider addon was created for typical webmaster without paying for extras.
- Maybe you should consider using your own .mp4 file.
Update info:
Indeed, Video Title and controls - can be legally hidden, but request using YouTube API key, so maybe in the future we will add support of that.