Well atm George St John is a 30 years debutant for Richmond , which puts him around top 20 of oldest debutants. But an 1889 birthdate would probably seem more likely as an 19 yr old debutant.
After Richmond in 1909 he got permit to Port Melbourne FOOTBALL. - VICTORIAN ASSOCIATION. - The Age (Melbourne, Vic. : 1854 - 1954) - 27 May 1909
Then as per Demonwiki went to Melbourne in 1911.
That article you quote is very specific about his cricket career, so if our footballer did that then he is surely our guy.
And , I assume the 1965 dying St John, had a brother called Stanley as per the article.
I can see how Rodgers would have selected the St John of 1934, as he was looking for George as a first name, but that may not have been his birth name.
