The beat the song is built on is a 2-bar phrase, played through bars 21-23, 25-27 and 29-31, and 5 more places -- 29.6% of every bar the kit plays. That is the spine of it; everything else is what happens around it.
It is played on ride, snare and kick, counted in sixteenth notes. On its own it scores 62 out of 100 -- a step up -- and the thing that decides that is the independence between the hands and the feet.
The whole song is 82 out of 100, so the beat is not the hard part: what costs you is everything around it, the joins and the fills.
A part this hard is not learned by playing it slowly and hoping. The room opens it on its simplest reduction -- the timekeeper alone, at 120 BPM -- and adds the notes back over 4 rungs, each with a tempo to reach and a gate to pass before the next.
Tempo goes 120, 141, 163 and 184 BPM, and the gate at each one is 8 loops in a row with no wrong note and no wobble in the time.
PRACTISE THIS BEAT →A 2-bar phrase on ride, snare and kick, in 4/4 at 184 BPM, counted in sixteenth notes. It is written out above, and it covers 29.6% of the bars the kit plays.
Bars 21-23, 25-27, 29-31 and 33-35, and 4 more places. The time is kept on the ride to start with, and it changes 17 times over the song.
62 out of 100 on its own -- a step up. The song as a whole is 82 out of 100. Hard, and what makes it hard is how many notes a second it asks for.