Sorry for the headaches. I have a knack for finding tricky situations. :-D
Have you guys considered that by removing Mongolia from going pro axis(except for a direct attack by USSR), you give the allies an advantage when deciding whether to invade a true neutral? Spain has merits for the allies, now the axis only get switz, sweden, turkery+Saudi(now, the only headaches for the allies-if they don’t have a mid east presence by UK), Afghan, a couple in S.africa, and some in S.America (typically out of reach of the axis). . The axis still have to add the Mongolia effect when they consider.
Mongolia would create a headache for China and USSR if Japan were contained, now that will no longer need to be considered. Outside of military reasons (position), income is also a factor. Turkey can be contested by a Mid East UK, so Sweden is the only one likely to remain in Axis hands. If effort and resources are diverted, all of S.America, portugal and Spain will likely be held by the USA. Without S.America it is 3 IPC vs 3 IPCs, with it becomes 9IPCs allies vs 3 IPCs axis.