While in the prison yard talking to the other inmate, the mole on the cheek of Martin Wells switches from the right side (18:39) to the left side (18:46) and then back to the right side (18:54).
When Martin Welles takes out the hidden camera, the lens cap is still on, and the camera is supposedly recording activity, which would be impossible.
This episode is set in Baltimore in early December, but in every outdoors scene, it appears to be sunny and warm out (this is especially noticeable in the outdoor prison yard scene). It would actually most likely be very cold outside and at least overcast, if not snowing.