In 2 different tanks, I have 2 goby pairs each with pistol shrimp. The larger goby of each pair is visible almost all the time. Much of the time both are visible.
With 2 pistol shrimps the pair might split apart and guard 1 shrimp each. I had 2 pistol shrimps in one tank with one goby pair and the 2 gobies lived apart for a long time, but even at opposite ends of the tank the gobies never fought. That pair is back together now. My guess is one of the shrimps might have died, but it’s difficult to know with the tiny candy cane pistol shrimps.