Codes code P0172 and P0191, fuel system?

Hello, was the high-pressure fuel pump replaced correctly? With the camshaft in the correct position, Ill post the service info on the pump replacement, but you will need to check live scan tool data on what the Fuel rail pressure sensor is reading to see what the PCM is seeing for a pressure reading. The reduced power message is due to the p0191 code. I assume the oil was full of gas? Or was the pump replaced just due to the p0172 rich code?
You should be able to do an injector balance test with a capable scan tool to see if any of them are leaking down. The P0191 code is a performance code for the pressure sensor, so the PCM is seeing a pressure it doesn't like. There are other codes that will set if the sensor is shorted to ground or power, so it sounds like there is still an actual issue with the fuel pressure. It needs to be checked on a scan tool, there should be two data PIDs to look at, the Desired Fuel Rail Pressure and Actual Fuel Rail pressure. There is also a pressure sensor for the low-pressure pump coming from the tank labelled just "Fuel Pressure", that's another data PID to look at, but the Fuel Rail pressure sensor is the high-pressure pump that setting the code. Theres some code setting criteria I'll post along with the pump installation info.

The first two diagrams are for the high-pressure pump install, and the rest are for the P0191 code, with what the pressure should be at idle and other circuit checking service info.