Can you get hold of vagcom ?, log requested verses actual fuel rail pressure. That will tell you if the pump is meeting demand, and also what is actually being requested. It could be the map is set to low settings and only trying to make 315bhp. And in fact you don't have a hardware issue.
I don't know what a stage 2+ revo map requests on average for fuel and boost, fuel should be requesting and meeting 130+ bar I would think, and boost I would have thought 1.4bar upwards ?. I am sure someone else with a 2+ revo will know.
I just fitted a rs4 valve to my car, the standard one bleeds off at 130bar so you might be unlucky and have one that bleeds really early in which case you rail pressure cannot meet the requested numbers.