Sorry, but to get to Sydney from Forbes and vice versa, it would be unlikely to travel via Dubbo, as that would be adding around nearly 200 miles extra to the journey. (Dubbo is north north west of Forbes, Sydney is almost due east of Forbes). Usual route in 1930's by road would be Forbes, Parkes, Orange, Bathurst, Lithgow, Katoomba, Penrith, Sydney. If by train, then insert Blayney as well. If Dubbo to Sydney, then Dubbo, Wellington, Orange, Bathurst, Lithgow or Dubbo, Wellington, Mudgee, Lithgow, etc .... doubtful if anyone would go Dubbo, Parkes, Forbes, Eugowra, Orange, Bathurst, Lithgow ... unless intending to spend up to four more hours on the road. Rail link did not connect Dubbo and Forbes either ...
If a death occurred in Forbes, then it should be registered as at Forbes. Henry Lawson (the poet) well his birth was registered at Forbes way back in 1867 ...
1937 NSW Electoral Roll John Huxley, Club House Hotel Forbes, labourer and back in 1903 the NSW Electoral roll has Frederick George Huxley on the Bogan Road, Forbes as a selector, and a Mary Huxley on the Bogan Road, at her domestic duties.
It is my understanding that it is possible that the returns for BDM from quite a number of central western townships in the pre WWII era may not have been received regularly by the NSW BDM Registrar General and that only limited attempts at reconciling the local registers with the Sydney register has been undertaken, ie... it is possible that the d.c. has been recorded at Forbes, but has not ever been lodged at the Sydney H.O. This also seems to be the case for Wagga, Young, Parkes, Peak Hill ... not all the clerical staff in the rural towns were full time employees devoted solely to recording bdm events, but were part timers attached to the sherrifs office or to the court houses etc.
If you think the death of Eliza/beth Huxley occurred in the Forbes District, have you considered contacting the Forbes Family Hisotry group, the last time I passed that way (on the way to Dubbo taking the long route of course with family touring central west places), the Forbes family history group were quite active with good records and plenty of space in the town library, next door to the court house and opposite a very pleasant park.
My notes show they had a PO box, perhaps it was this one
http://home.westserv.net.au/~ffhg/ I notice they are transcribing death notices from their local newspapers, and are back to the 1940's
Cheers JM