There is a lot I find wrong with your reply. It is the design cooperation that is the important factor in collaboration regardless of contractual details or position on a flow chart.
Somebody or some committee hired Colt at Old Elm and then hired Ross. If hiring by an owner defeats the collaborative spirit, how is the Old Elm scenario any different than Wilson hiring Pickering and later Flynn? How do you know that Colt did all the designing and Ross simply built the course to his plans. Is that a collaboration? If so, there is more of a collaboration between Raynor and Macdonald, Toomey and Flynn, Hatch/McGovern and Ross, Bell/Thomas, etc.
How is the Old Elm scenario different than Crump hiring Colt? I'll tell you, it is because Crump was actively involved in the design, more so than anyone else as was Wilson at the early and mid-stages of Merion. Colt wasn't the only contemporary collaborator at Pine Valley. Tillinghast, Alan and Hugh Wilson collaborated without compensation. Alison, Flynn and others had a hand in the development. Alison and Govan were likely paid, not sure about Flynn though he was made a member and Howard Toomey was on an executive committee.
When you make an outrageous statement such as Wilson hired a consultant (CBM) you lose all credibility. Firstly, CBM was an amateur in the strictest sense. I doubt you'll find any instance where he was a paid consultant. Secondly, there is no evidence that CBM or Whigham for that matter had any design input at Merion. Yes, they toured the property and declared the land acceptable for golf. Curious that, if he thought hard about it, the Ardmore Avenue constraint didn't bother CBM.
Wilson was the man most responsible for the early development of the East Course. He worked with a committee to come up with the routing and initial design. Sure, Wilson was the man most responsible for the initial effort but Fred Pickering (Flynn's brother-in-law) also had much to do with the initial product. Wilson's long-time collaboration with Flynn and then later Flynn on his own had much to do with the golf course we now know.