I'm born here and a citizen, however I don't have a passport, nor a copy of a birth certificate yet I need to prove I have a right to work here for a job.
From my look on the gov site, I can use a passport to get my birth certificate or a birth certificate to get a passport. Neither of which is any bloody help.
Have you got your identity verified on services vic? If so, you can request a new birth certificate and use your services vic as verification of identity. I just did this recently and the process was pretty smooth.
I'm only guessing really but I think they should be ok if the digital copies could be considered the original. For example I would expect that a printout of a digital bank statement would be something that you could get certified as you can pull up your bank website/app and display the 'original', but you might run into issues trying to convince someone that a photo of a card counts as it's clearly not the original form.