A bit more to chew on here from the May 19th, 1895 New York Sun. The article states that "the ideas of the golf players who petitioned the Park Board for the links have been followed as far as possible,
and the opinions of other experts obtained."
Additionally, the article states that Mr. Roosevelt, who had charge of the matter for the Park Commission, "had been in consultation with golf experts and contractors, and promptly closed a bargain with the lowest bidder."
Which begs the question of who in 1895 NY City would be classified as a "golf expert"? Frankly, I've seen the term used in the first decades in the states most often related to the playing ability of an individual, so it seems very possible that the article may be referring to Pyne, Peters, and the other charter members of the Mosholu Club. However, in this case, those men were already mentioned as "the...golf players who petitioned the Park Board", and leaves open the question of who the "other experts" were whose opinions were obtained.
Certainly from a playing perspective, the real "experts" in this country at that time would have primarily included professionals like Willie Dunn, Willie Davis, and Willie Park, Jr.. It's pretty clear from the timeline of the nearby Ardsley Club that Dunn would have been in the immediate area of Van Cortlandt undertaking that large project by the late spring of 1895.
Certainly nothing contemporaneously dispositive but certainly suggestive that more than Peters was involved in the creation.