You didn't read it at all, did you? Let me break it down one more time:
1 ) If players split, then they don't have to worry about playing a serious match; they still can, but (from their perspective) it's not a necessity, since the money is split anyway and it's irrelevant (to them) who gets 1st or 2nd.
2 ) If players don't have to worry about playing a serious match, they might not play the match the same way they would have it they did have to worry about playing to their highest potential (technically speaking, it's guaranteed that they won't play the same match, but I'm throwing a bone here).
3 ) If they don't play the same match that they would have if they were playing seriously, they might not do something that would have otherwise gotten them DQ'ed, something that a serious player might do (either on purpose or by accident) in a serious match; for instance, a player might not plank hard and might not go over the LGL, or a player might not try to sneak in an IDC where he otherwise would have, or any other thing a player could potentially be DQ'ed for.
4 ) If a player WOULD have been DQ'ed, he would have forfeited his ranking, and thus the cash that goes with it. Another player would have claimed the prize.
Therefore,
5 ) Splitting introduces a variable that cannot be accounted for (if a player playing seriously would have done something to be DQ'ed). This is a non-trivial variable, since disqualification would affect not only rankings, but how prizes would be awarded.
Thus, splitting cannot be tolerated; the act of splitting, by its very nature, allows players to manipulate the bracket in unforeseen ways, and all forms of bracket manipulation are strictly banned as cheating. Thus, splitting is cheating.
Again, quot erot demonstrandum. Want to try again, smart guy?