your fuel pump relay is obviously working. You will not be able to test it for a failure that causes the car to stall unless it is doing such.
The hesitations are not caused by an intermittant fuel pump relay but they might be caused by the OVP relay. But even though an OVP can cause Davids car not to run it is not likely to cause a KE car to die under acceleration.
Bosch Master, ASE Master, L1
33 years MB technician