We have carried out extensive semi-empirical QM dynamics of two variants of the miniprotein Trp-cage, TC5b and a more stable mutant TC10b. Small differences (e.g., Asp1 vs Asn1) in the sequence of the two peptides lead to differences in their thermal stability. From extensive SQM molecular dynamics of these proteins, we have found limited evidence that geometric coupling alone can distinguish the two peptides over the timescale studied. We have shown that differences are more apparent in the coupling of by-residue-summed charge distributions either from the full SQM MD run or from snapshots obtained with DFT. In particular, Asp1 in TC10b shows significantly enhanced coupling to both sequence-adjacent (i.e., Ala2) and more sequence-distant residues (i.e., Ala4, Lys8, and Ser20). These couplings are evident both from linear correlations as well as mutual information analysis. In all cases, Asp1 in TC10b samples a wide distribution of charges (ca. 0.4 a.u.) from weakly positive to significantly negative, highlighting potential limitations in the use of fixed-charge force fields. This greater flexibility of the charge distribution in Asp1 in comparison to Asn1 also leads to stronger overall coupling of the charge distributions of residues near the N-terminus. In comparison, geometric coupling appears comparable between TC10b and TC5b.