Thanks for looking. It's just an error with the birth details put in the deaths as well.
It is either Theophilus A. or Alexander T. The obit for his father sent me here:
The Register (Adelaide, SA : 1901 - 1929) - Thursday 2 April 1903
The Rev. John Peter Niquet, one of the oldest Lutheran ministers in Australia, who had lived at Mount Gambier for the last rune years with his son-in-law, the Rev. F. W. Matschoss, died on Monday night at the age of 91 years. ...
A little over nine years ago his wife died, and as he had then spent nearly 60 years in church sen-ice and his family were dispersed,- he retired and went to Mount Gambier, where he resided with his son-in-law. Three sons and six daughters survive him. The- sons are Messrs. C. AV. Niquet, of Middle Park, Melbourne; Alexander T. Niquet, of the United States of America ; and P. H. Niquet, of Mount Gambier. The daughters are Mrs. S. Olden, of Ballarat; Mrs. A. E. Roberts, of Yorke's Peninsula; Mrs. M. J. Reusch, of Tanunda; Mrs. E. W. Wishart, of Angaston; Mrs. Braun, wife of the Rev. Pastor Braun, of Hahndorf; and Mrs. F. W. Matschoss, of Mount Gambier.
I've checked all the children listed.
CAW = Charles Alexander Wesley
PH = Peter Henry
William and James died young.
Yes, 6 daughters survived him.