Can you confirm exactly what each fuel selector valve was set at (engines 1 through 4), and which fuel boost pumps were on?
The reason I ask is that if the fuel selector valves and boost pumps are configured properly, then there shouldn't be any issues with using the outboard tanks to feed the outboard engines,(Tank to engine and Manifold, Booster pumps ON) and also the the inboard engines too (Manifold to Engine).
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