Yes, Rhett. "Ollie" appears to be William's nickname derived from his Norwegian-born father
[who signed his naturalisation certificate as Oley, with address being 6 Eureka St, Richmond]
The 1903 electoral roll for Richmond North sub-district in electorate of Yarra shows a handful of McKelson names
(including William, and Oley) all residing at 6 Eureka Street.
I don't have an Encyclopaedia of AFL Footballers on me. If anyone has the book, what does it list his name in the book?