this looks like youtube kids from youtube itself, what are the differences between the two? I use youtube kids for my own kids on our iPads, which works somewhat fine, a bit clunky to add channels and to use it for offline watching though.
Perhaps this solves the fatal flaw that your kid has to have your google account signed into their tablet to watch yt kids. I got my child their own tablet, created a child Google account, signed into the Android tablet with it, and then I was unable to restrict what they watched. Best I could do was the young child algorithm, but there’s still so much trash.