Regrettably that is a fix that isn’t coming until 10.0.5, so that might be the loot issue you experienced since you should have had 2 drops, unless members of your raid group were saved to Heroic Dathea.
They also stated that with the return to group loot it was going to be possible that items no one could use would still drop. Their specific reference I believe was Bows can still drop even if there are no Hunters.
Edit: last statement was made sometime pre-launch during someones interviews, i couldnt tell you the exact one or when.