The branch is allegedly using the meat supplied by the Romero Butchers and thus serving human remains in guise of pizza. The Well Stacked Pizza Co. was the first restaurant in Little Haiti that was suspected for being linked to the meat exchange, long before the discovery of the Riverside Pavillion connection.
A strange glitch also occurs in the place when a Haitian gang member stands idle in front of the kitchen stove, giving an impression of being hexed. However, it's a technical fault within the game.
As for the human remains myth, it could be possible as a reference but the actual truth behind the myth is unknown, thus making the myth about the meat exchange unlikely.