A DQ is issued for safety violations and other unacceptable conduct. In the circumstances described the
competitor knows he is double-plugged and presumably intends to continue the stage, so although he has removed
part of his ear protection he has not
caused the loss of it because the inner plugs remain in place.
The competitor could have obtained equal or (likely) greater advantage by not wearing the ear muffs in the first place.
It would be difficult for the RO to know that the competitor removed the ear muffs to obtain a reshoot.
So there doesn't seem to be a safety issue, and while it may be a little gamey I doubt a DQ would be appropriate – it seems more like an error on the part of the RO for not realizing the competitor was using inner plugs.
5.4.3 If a Range Official notices that a competitor has lost or displaced their eye or ear protection during a course
of fire, or has commenced a course of fire without them, the Range Official must immediately stop the
competitor who will be required to reshoot the course of fire after the protective devices have been restored.
5.4.4 A competitor who inadvertently loses eye or ear protection during a course of fire, or commences a course of
fire without them, is entitled to stop, point their firearm in a safe direction and indicate the problem to the
Range Official, in which case the provisions of the previous rule will apply.
5.4.5 Any attempt to gain a competitive advantage by removing eye and/or ear protection during a course of fire
will be considered unsportsmanlike conduct (see Rule 10.6.2).
10.6.2 A competitor who is deemed by a Range Officer to have intentionally removed or caused the loss of eye or
ear protection in order to gain a competitive advantage will be disqualified.
Snapshot