Actually Inne might know very little as she's mostly just a hired gun, and one that Shady Sands is willing to sacrifice.
Not all raiders are the same. We normally think of them as the badguys in Max Max or other form of wasteland scum.
Some raiders are just cruel bandits, others are roving bandits by consequence. Others are different,.
The Vipers are from a community to the East of Vault 15. About the time Katrina left the Vault, this community was doing alright- small farms, relative peace. But shortly thereafter bad things began to happnen. Crops died, locusts killed their crops, and people began to disappear. Most of the Vipers moved away,the community came apart and the land turned barren.
Some left and have since disappeared. Alex has kept a few of them and has become a "roving bandit" primarily because he lacks a place to create a new home with what's left of his community. Few will welcome such a large group as a potential political threat. So they must live from day to day, moving about in search of food and other necessities.
We can argue that Alex could have have moved further off and settled and lived a peaceable existance. But this is the wasteland, and life is cruel to outsiders. Alex is here because he wants to keep his community together. Mostly, he thinks what ever happened is due to something at Vault 15.
The Rovers are a different matter. These are mostly hardcore bandits. As the Servents of Twilight, their cause seems almost religious. Alex suspects that the Rovers are not real bandits- independent entreprenaurs of violent acquisition, but really agents of someone else.
