Corner plot of the marginalised 1D and 2D posterior distributions of the free parameters optimised in our TUNER model fits. Dashed lines indicate the mean value and 16th and 84th percentile range for each parameter (from top to bottom and left to right: C_ff, molecular ISM gas to dust ratio, GDMR, molecular H₂ gas density log(n_H2) [cm⁻³], gas kinetic temperature T_K [K], emitting size radius (r) [pc], dust emissivity index (β_d), γ_T, turbulence dispersion velocity (ΔV) [km s⁻¹], dust temperature T_d [K] and [CO/H₂] gas-phase abundance).