I like the sheet though. I just feel it'd be nice if it all tied up together better.

One thing you could do - and this is just a suggestion - is have them been formed from a slave rebellion, like a Spartacus-type deal. So this is an army of former slaves that successful freed themselves amidst the chaos of the Legion civil war, and continue to operate and free slaves. They don't ask for payment, but their good deeds earn them supplies and shelter from supportive wastelanders. If you want to keep an NCR general as their leader, you could say the general was a prisoner of war and lead the rebellion.