Posterior distribution of the parameters q, p, M_discs, and M_DM(<15 kpc) that maximises the number of subclump stars on strongly resonantly trapped orbits and fits the rotation curve data by Eilers et al. (2019) and Zhou et al. (2023), in blue. MCMC steps of walkers that got stuck have been removed. The posterior parameter distribution shown in black corresponds to potentials in which at least 40% of the loL stars are on z-tube orbits. The peak value of this distribution, which we take as our best estimate, is indicated in green solid lines in all panels, and was determined using a kernel-density estimation. The 31.73% (68.27%) percentile of the data lower (higher) than the peak value is taken as the lower (upper) 1σ uncertainty and are indicated with dotted green lines in the panels showing histograms of the marginalised distributions. The grey lines in those same panels show the kernel-density estimation of the marginalised distributions.