Since the subject is of panelboard cabinets and the weep hole, would 312.5(A) and (C) be of interest?
A few weeks ago Joe T had some discussion of the definition of cable vs conductor.
Though, the text does not specifically state "Conductor" in 312.5 being secured to a cabinet, it does say "Conductors".
312.5(B) ends with " - - - and firmly secured to the enclosure." and 312.5(C) states in part " - - - each cable shall be secured to the cabinet, - - -."
Seem to me that any conductor or cable entering an enclosure needs to be secured to the enclosure so that any abuse to that/those conductors will not be transmitted to the conductor termination within the enclosure.
As an example see 527.4(I).
When that requirement was added to ( 305-4(i) ) the substantation was when secured to the enclosure, stress would not be transmitted to the terminal(s) within enclosure.
