I don't believe the rules explicitly cover this situation.
I assume that the TuG nearer to the chargers does not evade.
If so, there is no provision in the rules for the chargers to change their charge direction - so they will end up charging the TuG that is further away.
Because the nearer TuG stood to receive the charge, the charge path does not extend, so the TuG farther away cannot shoot. It will stand, skirmish or run away depending upon troop type or player choice.
If I am wrong I am sure someone will point it out!
Richard