shut shadow
I noticed while doing some testing that neither of these two items that are supposed to trigger on use of a mod trigger on certain weapons. Some are to be expected, like the Polygun, since it doesn't actually "activate" its mod, but others like the Corrupted Nebula should trigger it as they will trigger effects such as Archon's effects. A list of such weapons I've noticed don't trigger it but should are:
Corrupted Nebula
Twisted Arbalest
Monarch (On Shockwave Trigger)
There may be others as well, since I don't have every weapon.
hollow umbra
rustic viper
terse flame