Joint posterior PDFs for our three reference models, corresponding to the lensing-only models based on image positions (Img-MP (L), purple contours) and on extended surface brightness distributions (Esr2-MP_test (L), cyan contours), and to the joint modeling with strong lensing and dynamics (Img-MP (L/D), green contours). We focus on the most important mass parameters that describe the BGG and the extended group-scale halo. The three shaded areas on the joint PDFs show the 68.3%, 95.4%, and 99.7% credible regions. The 1D histograms show the marginalized PDFs for the selected mass parameters, and the vertical lines mark the 1σ confidence intervals. The model based on extended image fitting has narrower contours due to the large number of constraints from the lensed source morphologies.