Gonna throw a curve ball here: how about Germany? If the land only has limited European settlement until the late 19th century I can imagine Germany being ”payed off” with a territorially large but rather inhospitable colony, like they were with Namibia.
Totally plausible, but not particularly likely. If the British don't want to control it, which is easily achieved with a mid-18th century POD, then it's unlikely that anyone will display a huge interest in the late 18th/early 19th century. Whaling/sealing settlements will still probably emerge, possibly as the earliest European colonisation, and both the British and French would likely set up some small bases on the east or west coasts by the 1820's, but these do not necessarily need to be large to be functionally similar to the original Cape Town. For Germany to play a role though, it probably needs to unite earlier. Unless imperialism/colonialism are butterflied away completely, temperate disease-free Australia will almost certainly be carved up in the mid-19th century, before Africa. I could imagine large French, British, and Dutch settlements, and perhaps even some sort of American territory - Germany will need to be playing the game to get a piece though. Along with Germany, other less likely but plausible players under the right circumstances could include Spain, Portugal, and even Italy or Belgium. Australia is very big, and ultimately even the less productive parts will be cheap to control making it attractive even to prestige-seekers.