Hugh Wilson laid out Seaview, Donald Ross trapped it.
Is this correct ?
I'm disappointed that you haven't read my Hugh Wilson IMO articles.
In any case, after designing both courses at Merion, the course at Seaview, doing odds and ends at North Hills and Philmont, doing numerous layouts for the new public course at Cobb's Creek, all within about a 3 years span off the side of his Insurance Company desk, in December 1914 Hugh Wilson stepped down from his Green Chairman role at Merion, citing pressure of business.
Seaview had been open for play since about June of 1914, but Clarence Geist fell seriously ill, which delayed the grand opening until January 1915. Some commentary on the course was that it wasn't difficult enough, so in April 1915 Geist brought in Donald Ross to come up with suggestions and additional trapping. Some of his suggestions (based on his drawings that hang in the clubhouse) were implemented, many were not.
That same month of April 1915 Hugh Wilson and Francis Ouimet played against Geist and Wilfred Reid, with the former team winning and Ouimet setting the course record.
More details can be found here;http://golfclubatlas.com/cirba-mike-who-was-hugh-wilson-pg-2/
Also, it would be mistaken to think that the Wilson course before Ross had no trapping. This June 1914 article describes the golf course, which is much the same course folks play today, by and large.