I'd be dubious until you hear from someone who's done it. Gobies are placid little things until confronted by somebody who looks too much like/acts too much like them. Then it's nasty.
My yellow watchman (a pretty energetic sandsifter) gets along fine with highfin red-stripes, who live in others' burrows; firefish; chromis; mandarin; well, you can see my fish list. But I'd hesitate to bring in another variety of watchman. Another shrimp goby (a watchman is a shrimp goby but is a particular Kind of shrimp goby) is ok---as long as they're not both coveting the same tiger pistol shrimp. I once put a mirror near my tank and thought the yellow watchman was going to kill himself tryign to murder that 'fish."