I ran into this other formula at the same article:
2222222/((3036.93+2600)/9)^2 = 5,6648338721 = 5 (int)
5 * (1 - 1/14) = 4,6428571429
For calculating the payout of block: https://explorer.dash.org/b/C6881cFag
It works fine if you try it on that block. But, if I try it on, say...