David
I don't think that Ross traveled that much overseas, and when he did it was more for nostalgic reasons than a GCA pilgrimage. He played in the 1910 Open at St. Andrews, finishing in a tie for 8th, behind Braid, Herd, Duncan, Ray and others, but ahead of Taylor, Vardon, Ball, Massy, C. Hutchinson, Auchterlonie, Park, Jr. and Sayers. He also visited Dornoch in 1921 when he helped Sutherland and Taylor (I think) re-design the 1st and 2nd to deal with the modern ball. Overall, his early 20th century courses were mostly redesigned (by him) in the 1910-25 period, again due to the realities of the modern ball.
I would speculate that CBM's influence was based partly on his bluster and self-promotion, as well as the fact that he built NGLA at the time when it was becoming obvious that the old courses (in the States and in GBI) were inadequate given the new technology.
Even if they did happen to meet (given that DJR finished in the top 10 at 4 of the 6 US Opens in the 1902-1907 period, their meeting was likely), I doubt he and Ross would have gotten along.
Rich