Comparison between the observed PILS spectrum and the synthetic spectra obtained using the (old) spectroscopic data utilized in Jørgensen et al. (2018) (in blue) and the current spectroscopy (in red). The two synthetic spectra at an offset of 0.6 Jy beam⁻¹ correspond to the prediction from the fit of the 2018 paper (solid blue curve) and current spectroscopy (dashed red curve), adopting the excitation temperature of 300 K from Jørgensen et al. (2018) and the column density from that same paper corrected for the factor of four error discussed in Sec. 5 (N = 4.5 × 10¹⁶ cm⁻²). These two synthetic spectra are virtually identical except for two high excitation transitions at 362.7685 and 362.8805 GHz, where the new spectroscopic model demonstrates one clearly overpredicted transition (marked by an arrow). The synthetic spectrum at an offset of 0 Jy/beam correspond to the prediction with the lower inferred excitation temperature from the analysis summarized in Table 2, shown with a red curve. As can be seen, this spectrum matches well the high excitation 362.7685 and 362.8805 GHz transitions, which were not included in the old spectroscopy. These two lines come out at appropriate intensities in comparison to the observations within the uncertainties of the model.