Stronghammer Signet not dropping in PvE

I’ve been running the Crypt non-stop for the past week looking for a Stronghammer Signet to complete the Armorer Campaign and so far haven’t seen a single one. I’ve been bringing 4 Skull keys and opening 3-4 Skull chests every raid as well as killing as many enemies as I can and the elite Wraith. Nothing.

I think your PvE loot scarcity policy might be keeping players from completing this objective. Please look into it.