They have buses,that run from Gulfport to New Orleans. Not sure from the mall though.
The local casino's have buses to and from New Orleans. And, the gas station on the corner by the Outlet Mall has a Greyhound station.
I didn't see a sign where a bus would stop
I don't know. Megabus' website might have a route you can get on
Thanks! Your answer is awaiting moderation.