Dan:
I've never heard of Park being associated with Sadaquada, and would be interested in seeing where that information originated. The Jan. 1896 edition of The Golfer noted that the course was laid out with 9 holes by Horace Rawlins in late 1895, which corresponds with all of the early reports on the course.
To answer the question, 6 holes was not that unusual. There are a number of early courses (1890's) that started with less than the normal 9 (there were very few 18 hole courses being built that early).
Many, but not all, of these courses named the holes. Take a look at the 1900 Harpers Guide for examples. The concept of naming holes seems to have faded away as the Golden Age really got going in the 1920's, with the notable exception of all the MacRaynor courses where the holes retained the template names.
Hope this helps,
Sven