I have 2 clown gobies that could care less about the dsb. I have had yellow watchman gobies that did not disturb the sandbed. There some gobies that you will see under live rock in caves but they did not do the digging. Those gobies form a relationship with a pistol shrimp, and the shrimp does the digging.
I've never had any issues whatsoever with my lawnmower blennies.... they stir up debris on rocks, but they don't dig in the sandbed.
Another blenny I was recently given, on the other hand, digs a new hole every day. My water quality is quite good at the moment, but you could never tell from the water clarity Dunno what kind he is, but he looks very similar to the lawnmowers except for he's a nearly-solid dark brown.
In conclusion, go with a lawnmower blenny. It's not a goby, but it's close!