I believe it IS Hibbertia obtusifolia. The globose buds and obviate leaves are right for that species. I agree that it does look unusually green, but that may be a function of the light in the photo. See the photo in the below link. Plantnet says it is very variable. http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Hibbertia~obtusifolia