A Vr of 112 knots for a not fully loaded but well and by far not empty A321 should have rung a bell as early as at performance computation stage. The whole set of performance data was invalid.
Also, as people well acquainted with the matter say, Wizz air have a highly customised normal checklist which does not include an after takeoff checklist. Surely reading the standard Airbus checklist to the line after flaps retraction wouldn't have allowed them to climb to 5000 with the gear down?