Results from testing of our method in Sect. 3.3, showing we reproduce the large range in metallicity between the Milky Way and the SMC for 5 out of the 4865 realisations. Top: All the ‘most likely’ realisations (in grey) and those that recover a 0.6 dex difference in metallicity between both of the Milky Way clouds and the SMC cloud (in green). Bottom: Histogram of the total hydrogen gas distributions for these realisations.