Paul,
I don't know about Indian Hill in Winnetka, and for some reaon, I thought that it was Flynn, but my memory is fuzzy.
As to Ross and Colt working together at Old Elm, Killian and Nugent did a few greens while I was employed there, and when working there, I heard that the club linterviewed both, and unable to decide, locked the two of them in a room until they came out with a joint routing. Ross walked away after that.
Later, a spinoff group formed Shoreacres, and neither would have anything to do with them, and Raynor got the job after they declined.
The story on Bob O Link was a little different in that Ross supposedly had the routing done before WWI, and then had too many projects starting up after the war, and agreed to /arranged for or simply walked away when he had to much work, and Colt and Company did the actual construction.
Of course, given the scarcity of club records, those stories could have some, none or complete truthfulness about them. I will leave it to historians to figure out.