As Respawn puts it, "You can play with other banned players in something that will resemble the Wimbledon of aimbot contests. Hopefully the aimbot cheat you paid for really is the best, or these all-cheater matches could be frustrating for you. Good luck."
If you're not banned and invite a banned friend into your party, you'll all end up playing in the all-cheater pool. Respawn promises that playing with cheaters won't raise your risk of getting banned. Only cheating can do that.
If you think you've been unfairly banned, Respawn says to hit up email@example.com.