Ran a Duviri Experience round on Steel Path, took about an hour. Neither Clamps nor Banes dropped.
Full public squad, I was running Baruuk Prime. We did three UC portals and Kullervo before killing the worm. I was downed at the moment the worm died, might be the reason for the lost rewards.
This occurred shortly after the 33.5.4 hotfix, and I did reboot before joining the mission.
We had around 25 decrees, won all our UC side missions, and I ended the mission with all three new arcanes in my drops and all the other resources I'd amassed but neither clamps nor banes.
At least one other player thinks he did get them, but we can't confirm because Last Mission Results screen is blank. (another separate bug, I suppose).
P.s. what's with the limited (but required) Tag options? Obviously this has nothing to do with Performance, but there's no option for Game Functionality.