While density functional theory (DFT) provides reasonable molecular geometries, the determination of the ground spin state and associated energetics is highly dependent on the choice of DFT functional. Among the functionals employed in our study, only the TPSSh-D3 functional exhibited close agreement with the CASPT2 energetics, whereas significant deviations were observed with other functionals. In a nutshell, this comprehensive XMS-CASPT2 investigation has contributed to the long-standing debate regarding the molecular structure and spin of the ground state of copper corrole systems. While DFT structures and relative energies at minima are reasonably well described, the choice of functional to describe the energy surfaces connecting the critical points is much more challenging. By using a multireference method, the nature of the molecular geometries can be obtained for the correct electronic state, eliminating the need to first understand the electronic structure and then choose the DFT approach that most closely approximates the correct state.