Based on what I can see looking at the fish, and based on the recent rash of them coming in, I'm inclined to say H. tanzaniae. These fish don't show color well over a light background so that makes it hard to identify as well.
Vittatus and tanzaniae are
extremely closely related and at this size can be very hard to tell apart. The only distinguishing factors at this size are that tanzaniae has a longer jaw that vittatus and different coloration, and with the light background its hard to see colors. He does appear to have the long jaw however.
Data we need to identify:
Adipose fin viewed under bright light: black or steel blue?
Paired fins: tipped in white or colorless?
Can you get a lateral line scale count?
Compare your fish to my tanzaniae when I first got him:
No lights, can't see colors:
With lights on, illustrates the blue adipose well:
Hope this helps!