This is the first I've seen Park with Ashbourne. CC of AC, Green Valley and Philmont were all Park designs from around 1920, 1921, 1922. When Park was designing Green Valley Philadelphia Cricket called him for advise on a second 18. I have no idea if he designed anything at PCC or not.
Park really didn't have his own construction crew, the closest thing would be Peterson, Sinclaire and Miller, a seed merchant out of NYC. His courses were built by a wide range of folks, which is why there is inconsistancy quality-wise from course to course.
I think Park's last advertisement which listed all his courses came in 1922, prior to Ashbourne. Later in 1923 he had a vervous breakdown and left the country.