The quasi-2D Kagome metals AV₃Sb₅ (A = Cs, K, Rb) have emerged as a rich platform to explore the interplay between geometric frustration, nontrivial band topology and strong electronic correlations which stems from a series of van-Hove singularities. This family of materials is characterized by the absence of any localized magnetic moments, with superconductivity emerging from a charge density wave state with broken time reversal symmetry. Superconductivity with broken time reversal symmetry was seen in μSR, Kerr effect and superconducting diode effect studies in some members of this family. The superconducting order-parameter in AV₃Sb_5-xSn_x is particularly intriguing, with theoretical proposals ranging from sign-changing s_± to chiral d+id pairing symmetries with increasing doping. Here, we investigate the doping evolution in RbV₃Sb_5-xSn_x using spectroscopic-imaging scanning tunneling microscopy. Close to optimal doping (x = 0.3), we uncover clear evidence for a two-gap superconducting order parameter, revealed both by distinct spectroscopic features and quasi-particle interference within the larger gap energies. Atomic-scale imaging of the Sb honeycomb layer further identifies two types of defect-induced bound states, absent in the pristine and lightly doped compounds. A systematic comparison between experiment and theory for the effects of magnetic and non-magnetic impurities on superconductivity allows us to identify the chiral state d+id as the order parameter in almost optimally doped RbV₃Sb_5-xSn_x.