Unfortunately I do not have a recording of this as it was off OBS. During the indoor section of Stronghold leading up to Urias (hammer bro), I flashbang stunned the first armored Lycan to drop down, and this apparently caused all other enemies to go dormant.

Have not been able to replicate, but basically nothing else spawned. I saved at the typewriter before Urias. As I expected, Urias also did not spawn. Restarting did nothing, but loading directly from the typewriter fixed it and let Urias spawn. If replicated, you could potentially just bypass the gauntlet without using anything and then force spawn Urias with a reload, saving supplies and collecting whatever you want in the meantime.

Should probably mentioned this was while practicing Village of Shadows.