You can bring a bottle of Rimmer's ale to the major: if you talk to him after doing that, he will give you a password you can use in the dwarven mines.
Without giving you any spoilers, I can tell you that bringing the beer won't solve the quest: you have to do some other things after talking to this dwarf.

I am in blood
Stepp'd in so far, that, should I wade no more,
Returning were as tedious as go o'er.