From the introduction:
Brother Thaddeus comes to see the party at the Steel Horse. He has an unusual request. It seems the Brotherhood doesn't wish to give away such a rare and valuable component as the one needed by the party. However, the group has little to offer in trade, as Thaddeus expected. One item greatly in demand by the Brotherhood is available in Vegas, but is unfortunately under the control of another group. The Brotherhood has attempted to equitably trade for this item, but its current owners are adamant that they will not give it up. The Brotherhood rules out any direct action on their part to take the prize. If the prize happens to be made available for trade by the party, however, the Brotherhood would swap the required part for it.