How warm was the engine when you made that vid? Sounds like a good bit of piston slap and a little odd but much more slap then I get from my street racer with big clearances starting a 10 above which I do every winter.

It also has some odd noises and it looks like the motor bucks a hair with the odd sound.

I would of changed oil sooner but you could still send in a sample and see if its fuel diluted or has coolant in it with little cost.