Dash was working as a bounty hunter, tracking a Kel Dor hotshot pilot named Yalt Tarasos to Seregar. Yalt knew Dash and his team was coming, and laid a trap for them, causing the ship to crash down on the planet below.

Dash was the only survivor, and had to learn to live in the wilds of the planet. Several years passed without a living soul, when suddenly a ship landed. Turned out it was a mercenary outfit hired to find an old smuggler's stash on the planet. Dash was able to leverage his services as a scout/guide in exchange for a ride off the planet.

The outfit found him so useful that they kept him on after the job was completed. Or they could have set him up with another crew. Or he ran with them for a while, building up a reputation before joining a new crew. Depending on what fits with the other characters.