Coolsjn, I would not do this to yourself. Forget it for now, and focus on all the good things about KEHS and how it best fits your DD. If you get a an offer, then go for it. The CHG is a bridge than you cannot cross till 1/3 or to reverse look at it, you cannot turn it down till at least 1/3.
So don't waste your time, do everything you can to get KEHS in the bag and make it an easy decision to drop CHG. If you change your mind and eventually go with CHG no one but you will ever know, but don't muddle your thinking about KEHS without good cause
My DD is keen on CHG cause few of her friends going there but tbh they are senior and in reality she will see them only 5 - 10 minutes a day max as everyone will be busy with their class / activity etc.
End of the day no matter how much financial help KEHS offers it will still be expensive and bit tougher in terms to daily commute to school. from this point only CHG outweights KEHS however I know KEHS will have loads to offer than I think and I am trying to find out more about it.
thats why I set CHG as a benchmark to see what extra we get from KEHS