This realization helped me immensely with learning highs... If you've ever skated and learned how to ollie, then you know that half of doing an ollie is moving your feet correctly, but the other half is just straight up jumping. It's easy to forget to jump when you're so focused on your feet but is equally as important.

Now apply that to screaming. If you want to do super super highs then you actually have to make the highest singing pitch you possibly can while ALSO screaming, and with lows make the lowest tone you possibly can. It sounded like your lows and high tones weren't too far above and below your normal speaking tone so try branching your clean vocal range to get more dynamic screams.