Updating a marriage certificate

Hey all, just looking for some advice. I'm not sure if this is the right place but any help would be greatly appreciated.

My wife is looking to change her name to my new legal name, however I have completed a legal name change after marriage, so my legal last name is now different to what is on the marriage certificate.

For the first step, we went down to main roads to try and get her last name changed on her license. We brang along the marriage certificate and my new birth certificate with the backing on it that in Qld doubles as a proof of name change document as it details my old, new and proof of name change.

We figured this might be enough as it shows our marriage, last names and my proof of name change. However this was not enough and main roads told us we need to update the marriage certificate itself.

We have talked to department of births, marriages and deaths they have told us it is impossible to alter a marriage certificate. So we are led to believe the only option for my wife to change her name is now to also do a legal name change, before we do that we are just trying to triple-confirm. because this seems to be an uncommon thing and we kind of got the 'move along' feeling from the government departments.