Louise Elizabeth Bamberger-my great great grandfathers first child

From copies of various certificates I have learnt the following:

She married Frank Taylor 28 Dec 1880 in Rockhampton
She married Frank Taylor 22 October 1880 in Rockhampton
Frank is shown as a stockman on various certificates
I have not been able to find a record of either marriage date. Are the QLD BMD records online complete?

Her first born child with Frank was born at Nive Saw Mills 7th. September 1881 and died 15 mins later. On the back of this childs death certificate there is a question as to whether Elizabeth is the mother or widow of Louis Bamberger drowned with Mails(Mais?)between Maryborough and Bundaberg about 1878. Does anyone know what Mails or Mais might mean?
Does anyone know more about Nive Saw Mills? I did a google but didn't find anything
Your help is appreciated!