Tom MacW
Good reserach regarding Watson and Ross. I would pick a couple of nits, however, namely:
1. The info from St. Andrews only indicates that Willie W. attended the University for a couple of years, not that he was a "graduate.". There is no mention of him graduating, which I am sure they would have provided if he had in fact graduated. No big deal, as even Tiger Woods was unwilling to spend his full 4 years at Uni when fame and fortune beckoned in the golfing world....
2. Ross's manifest info does not include the whole summer of 1910, as he arrived back in the USA on September 3, so it is not impossible that he was in Minnesota in the summer of 1910 as the Ordway diary notes. It is also possible that he may have visited in May or late September/early October, which many people might mistake for "summer" if the weather was felciitous. Or, maybe Ms. Ordway just had the year wrong by a year or two, (as did the esteemed Alan Wilson)......
Keep on researching, as you are adding to our and, I would suspect, Dr. Mammel's understanding, even if not yet convincing some of us as to to the conclusions you draw from your and other information.
3.