Fig. presents the cavity frequency dependence of the VSC-modified rate profile, with the same parameters used in Fig. . The open circles and the guiding thin lines are results obtained from the HEOM simulations (identical to those presented in Fig. ), and the thick solid lines are the results obtained from the FGR expression using Eq. 41 scaled by a factor of 0.4. Although not in perfect agreement, the FGR rate exactly predicted the resonant behavior at ω c = ω 0 , and provided semiquantitative estimations for the peak height and width of the rate profile, when the light-matter coupling strength η c < 0.05 (or Ω R < 25 cm -1 ). For η c > 0.05, the FGR expression still provides the resonant behavior but is further deviating from the HEOM results in terms of the magnitude due to the breakdown of FGR.