I highly doubt that the fish is a pundamilia red flank. First off, they are very rare in the states and chances of getting them are very hard. The horizontal bar is too evident on the fish pictured and it lacks the vertical bars for what the red flank is known for, similar to that of the pundamilia nyererei.
Here is Greg's article on the red flank. It gives you the identifiers and the description of the fish.
Pundamilia sp "red flank" is a "nyererei" type species. Males grow to 10cm while the females reach 9cm. The head coloration is a dull gray to steel blue color. The throat is shaded lighter to almost white. The bottom lip is lighter colored than the upper. A bar runs from the corner of the mouth into the eye and thickens as it streaks around the head. A light barely distinguishable bar runs between the eyes halfway up the forehead. An orange spot adorns the gill plate; and is more distinct in some individuals than others.
The underside of the body is a red orange coloration fading lighter to yellow towards the tail. Seven black bars run from the belly right to the dorsal region on the back. A red hue is present throughout the body but much lighter along the belly and darkening towards the dorsal. The region of the caudal peduncle is dark blue black.
The dorsal fin is turquoise in some individuals and blue in others. Dorsal has a red border running along the top in a thin line. The beginning of each ray is red and fades to the blue color halfway up the fin. The tail fin is black in the region immediately extending from the caudal peduncle and deep red for the remaining portion. The anal fin is the same red coloration as the tail with five to seven yellow egg spots. The pelvic fins are black, fading to red in the upper back section.
personally I think it looks most like the flameback but the pics are not clear enough to tell for sure... by the way how do these differ from the thickskin?