Hammer of Kamasa softlock #118620876

Completing the molten vault as one of a duo produces only one Hammer of Kamasa.
Handing that in does not advance the quest or give rewards to the player who did not pick up the hammer. (the party leader and instance owner did not get credit in this case).

Repeating the vault solo to catch up that quest produces a weird soft-lock state where no hammer drops and the character cannot move. The game is not frozen and burst into life for a couple of seconds every minute or so but the quest does not advance because there is no hammer to pick up.

A third attempt on another fresh instance of the map also drops no hammer but did not reproduce the effect of the character being frozen.