The same IR routes have been charted for many decades. IR-111 has been in use at least since 2000 (and undoubtedly many years previously) with hundreds of sorties in that year alone: https://www.globalsecurity.org/military/library/report/enviro/rbti/VOL1/Vol1.pdf
IR routes are used in routine military training and there's exactly nothing secret about them as the document above lists sorties in great detail. You can sit underneath one and watch flights going overhead frequently depending on the training schedule of the associated AFB. Going by the report from 2000 there's on average more than one flight per day that flies that route.
The TFR only goes to about 3,000' over the mountains and above that flights are completely unrestricted. Anyone with a plane capable of flying that high could fly over the entire area all they want and undoubtedly countless fire sightseers and news organizations are doing just that. The idea the military would even try to hide a plane crash is more than just a bit far fetched.
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