We track magnon dispersion and lifetime renormalization across the metal–insulator transition, allowing us to uncover a crossover from a chirality-selective dissipation of magnon modes to coherent yet strongly deformed chiral magnon branches with significantly enhanced splitting. Using slave-boson theory for the Hubbard model on the checkerboard lattice, we calculate dynamical altermagnetic spin susceptibilities from the metallic to the insulating regime. We further support our results with complementary dynamical mean-field theory calculations. Our formalism provides a quantitative framework for describing collective spin dynamics in correlated altermagnets.