Third possibility: they don't have the data on hand anymore to correct the figures with... It was a 2013 paper, after all. In their reaction statement they also

Third possibility: they don't have the data on hand anymore to correct the figures with... It was a 2013 paper, after all. In their reaction statement they also provide a new citation which re-ran the experiments: "Confirmatory experimentation has now been performed and the results can be found in a preprint article posted on bioRxiv, ‘Homeostatic responses to hypoxia by the carotid body and adrenal medulla are based on mutual antagonism between HIF-1α and HIF-2α’"