We obtained retarded Green's functions for massless scalar fields in the background of nearextreme, near-horizon rotating charged black hole of five-dimensional minimal gauged supergravity in Phys. Rev. D 84, 044018 (2011). For general nonextreme black holes, we also derived the radial part of the massless Klein-Gordon equation with zero azimuthal-angle eigenvalues, and showed that it is a general Heun's equation with a regular singularity at each horizon u k (k = 1, 2, 3) and at infinity. We derived explicitly that the residuum of a pole at each u k is associated with the surface gravity there. In this addendum, probing regular singularities at each u k we complete the derivation of the full radial equation with nonzero azimuthal-angle eigenvalues. The residua now include modifications by the angular velocities at respective horizons. This result completes the analysis of the wave equation for the massless Klein-Gordon equation for the general rotating charged black hole of five-dimensional minimal gauged supergravity.