With an entire Covenant regiment hot on the trail of their comrades, Dutch and Romeo don't have a lot of options...the radios are out, so they can't alert their CO as to what's behind them, and they don't have enough firepower to take the Covenant force out on their own. But... hey, what's this here? A lightly guarded Covenant Drop Ship? But who'd be stupid enough to steal a Drop Ship? Two of the UNSC's finest, perhaps?