Post #3: I obviously mistakenly thought that old chestnut had died a natural death some considerable time ago!
As already verified, it is indeed a skink, the species being Egernia striolata, commonly referred to as the “Tree Skink”. While it regularly utilises hollow trees and exfoliating bark for shelter, it is equally at home in rocky environments that provide crevices for shelter. They are social species, often occurring in pairs, family groups or multiple pairs with some unpaired members.