Please do consider contacting St Johns C of E re their parish register for Agnes marriage

it will at least give you the info that NSW BDM did not receive from Rev Gunther at the time he sent through his summary info.
Re Frances FIRTH’s dc transcription:
Witnesses : Thomas Wesley, William Caplin
Undertaker S Moore
Rev James Gunther, C of E
Medical Attendant W KingNSW ER 1870 MUDGEE
Thomas WESTLEY, of Mudgee household, Perry St,
John WESTLEY, of Talbragar, freehold, Perry St
William KING, of Mudgee, household, Church St
Samuel MOORE, of Mudgee, freehold of Church St
May I mention a co—incidence the medical attendant “W King” and the middle name for Walter SHERRY’s wife … Amy King, as per the headstone and the cutting from the newspapers, as per Trove (I leave it to you to follow through, Walter Sherry then re-married).
http://austcemindex.com/inscription.php?id=8647376 From a Directory for 1867
W SHERRY, tailor, Mudgee
From Grevilles 1875 directory MUDGEE
William CAPLIN, sexton, Church Street
Cheers, JM