Hi,
Qld BDM is online and covers the years you are looking for.
https://www.bdm.qld.gov.au/IndexSearch/mainMenuSubmit.m?main...

Electoral Rolls are also here on Ancestry to 1954.

There are sooo many William CAMPBELL for me to see right off which one is yours on any searches..I will see if he had a middle name or if I can work it out..

Kellie