Thank you to those who were able to help with my inquiry. There is a letter from a relative of William Reed and she says in the letter that William was born in Sussex, but there are other things mentioned that we know to be incorrect, so that could be one of them!
Agnes did marry twice, firstly to William Earl in 1862. He died at the "Squatters Arms" in 1868 and then Agnes remarried - to William Reed.
Agnes Reed was interred at the Collarenebri cemetery and their records show she was "w/William", but he is certainly not with her. If he died at the Benevolent Asylum in Sydney, no doubt his body would not have been taken back to his home town.
Thanks again to all,
Dunscore