If what you describe is correct, if the belt snaps, the fuel pump will stop and so the cylinders will not be injected with fuel.
The simple answer is the engine will stop.
As long as the broken belt can’t get to the timing chain and cause it damage or to come off, then there should be no mechanical damage to the engine. If a new belt is fitted correctly the ...
The timing is the controlled by the chain so the valve timing will only be affected by excessive wear or breakage of that chain.
The belt driving the fuel pump controls the fuel pump and won’t affect timing but will affect fuel delivery.