As the Courier follows the trail left behind by Benny and his Great Khans entourage, they find a unit of NCR Army soldiers locked in a stalemate with the Khans. As luck would have it, these are the Great Khans they're looking. They've are under siege in the ruins, surrounded by Lieutenant Monroe's men. Unfortunately, the soldiers are forced to stay put: The Khans have taken a number of their comrades hostage. The entire situation has gone from bad to worse: After exchanging fire with a Novac patrol, the Khans fell back. However, rather than wait for reinforcements to arrive, the patrol pursued the Khans into the ruins, getting caught in the crossfire. Most of them got out, but two privates got captured by the Khans. Since then, the situation has been a stalemate, as the troopers cannot attack without risking the lives of their fellow soldiers.
The quest is given automatically after talking to Lieutenant Monroe at the entrance to the Boulder City ruins. The player can offer to negotiate with the Khans' leader, which will make the Khans non-hostile and allow the player to reach him. Conversely, if they decide to sneak in or participate in the attack, the Khans will be hostile.
There are three main ways to accomplish this quest:
Talk to the Lieutenant, offer to negotiate, then talk Jessup down with Speech 45. Jessup will agree to letting the hostages go as a sign of good will, expecting Monroe to let the Khans leave unmolested. However, the lieutenant receives orders to attack the Khans in the meantime, with the brass writing the hostages off as acceptable casualties. The player can lean on his honor if the Khans let the soldiers go or leave the matter up to him (in this case, he goes through with the orders). If the hostages weren't released, the player has to bribe him with 500 caps towards the soldiers' families fund (400 with Barter 45).
If the player cannot convince Jessup to let the hostages go, then they must bribe the Lieutenant.
Sneak in, release the hostages, then either wipe the Khans out with the NCR or wait for the Army to mop up.
Kill the NCR soldiers for Jessup, allowing the Khans to leave unmolested.
Meet with Jessup, leader of the Great Khans in Boulder City.
Negotiate for the release of the NCR hostages.
Return to Lieutenant Monroe and inform him that you've worked out a deal with the Great Khans.
Siding with the Khans
Help the Great Khans kill all the NCR troops in the Boulder City ruins.
Tell Jessup the Great Khans are free to go.
PCXbox 360 Skipping Boulder City and going straight to Vegas may break Jessup's dialogue permanently.