Thus, we evaluated the new CH_4_CC_3 parametrization on a small model system used to study hydride transfer reactions in organic chemistry, where the substrate exhibits distinct structural features compared to Ccr's substrate (see Figure in the SI). This model involves a reaction between a derivative of 1,4-dihydropyridine, specifically diethyl-1,2,6trimethyl-1,4-dihydropyridine-3,5-dicarboxylate (a member of the Hantzsch ester family), and the substrate benzyne. The system was chosen for two main reasons: first, due to its structural similarities to NAD(P)H, where the 1,4-dihydropyridine ring represents the core of the molecule; and second, because it features distinct structural elements, such as an unsaturated substrate (benzyne) that is sufficiently different from crotonyl-CoA in Ccr. Our calculations reveal that the original DFTB3 parametrization also yields a severe underestimation of the barrier and the creation of a fictitious minimum near the transition state (TS).