[Miller]

Luck/Item Drop Boosts only affects if a drop even drops in the first place and it's party wide. There's no individual calculation for each party member, otherwise we'd be seeing a lot more 10*s.
(ie: If you kill one firespitter, it can only ever be one reactive armor across the entire party)

Drops are randomly split across the party afterward as well, it's not weighted towards the one with luck.

With that said, yeah there should be at least a minimum of 1 gold bar if not the full reward given to the party.