We report a joint experimental/theoretical study of a series of group IV atom-doped gold anion clusters MAu16- (M = Si, Ge, Sn). We find that their global minima possess exohedral structures, which are dominated by the strong M-Au local interactions reminiscent of the MAU(4) clusters. In particular, a dangling Au atom is observed in the low-lying isomers of SiAu16- which confirms the Au/H analogy reported earlier in Si-Au mixed clusters. The nature of the dopant-Au local interactions is a critical factor in determining whether an impurity atom can be used to dope the golden cages.