Hello Tom,
I really enjoy watching and photographing jawfish. Since the yellowheaded jawfish typically stays vertical in the mouth of or just above its den, except for those quick darts to grab a bit to eat, I encourage you to photograph them vertically and get real close. Once I know where a jawfish can be found and become hungry for a good image, I resign myself to the fact that it may be a "jawfish only" dive. This means that I prepare myself mentally to spend the whole dive concentrating on the jawfish, though it may only take a portion of the dive.
Patience is certainly a virture here. The first objective (after locating the fish, of course) is to try to make the jawfish as comfortable with your presence and the camera as possible. If you lay in the sand about 10 feet from the prospective den (with your camera visible), just breathe slowly for awhile and then move a bit closer, the jawfish will gradually become more brave.
After he begins to think that your not trying to make a jawfish sandwich, the next step is to try to get him used to the strobes. So, taking a few shots, even if your not as close as you eventually hope to get and then deleting them can help. The goal is to let the jawfish know that your not out for a snack AND you have numerous funky eyes, which sometimes pulsate.
When you are finally in position, try not to disturb the surrounding sand anymore than is necessary because you will either have to wait until the sand settles again or get used to the fact that backscatter will degrade your images. Once you begin taking what you hope to be keeper shots, do not rush your motions or increase your breathing. Space your shots so the jawfish does not become agitated.
One last thought is to ask a local, knowledgeable dive guide when the jawfish are most like to be breeding. Since the male stores the eggs in his mouth, you might be able to get close to prospective father. The resulting shots can be spectacular.
I hope this helps. Please post another shot if you try it again.
Scott