I know there are some indexes for applications in State records but I'm not sure how far they go. There were actually very few divorces. There were more petitions for divorce and they had to be on grounds of desertion or adultery and had to have witnesses, respondents etc and very few were finalised. Check the marriage certificate for SA with Albert and see if there is any notation there and also the WA one with Grenvold. I notice on the marriage index she is Grace Stevens, i wonder if she should have been Hooper if she was divorced (married in her maiden name, but showing former names).
My great aunt married in 1910 and then in 1918, without divorce - just used a fake name with her initials for the second.
My great grandfather's first wife married 2 more men, all living and not divorced (3 marriages) so my great-grandfather also remarried after that, no divorce. They all used their real names but were all i the 1800's. People didn't carry any ID.