It still boils down to this:
1) The UK (which I include its commonwealth countries) could not have been invaded by Germany OR Russia
2) Germany might have defeated Russia without being distracted by US material and forces.
3) Germany might have been defeated by Russia simply by attrition.
4) Either way, the UK speaks English and all of the rest of Europe speaks German or Russian.
5) The UK and its forces from around the world could not have defeated Germany through an invasion.