Does anyone offer Bermuda grass sod removal in DFW?
Any suggestions on "barriers" to prevent Bermuda grass
from invading my vegetable garden?

I'd love for someone to come and "remove" all of our "grass" too! Smothering can only happen as fast as I can find giant sheets of cardboard or other suitable materials.

A hard barrier like landscape timbers or bricks should be enough to stop Bermuda, just trim often enough so it doesn't go over. Severing all around the edge will help make sure nothing's still connected to plants outside the garden area, then pull/dig up everything within the garden, making sure to get all of the roots. Mow with the chute aiming away from beds so it doesn't throw grass seed into them. Hopefully you don't have torpedo grass!

Years ago we had a Bermuda grass lawn removed. They just used a sod cutter and then rolled it up like sod you buy. It took more than 10 years for the roots to stop sending up grasses. I had grass in every bed I was trying to grow. It will grow from the slightest piece of the root. Bermuda is very hard to be rid of completely. Using Roundup over and over finally did get rid of most of it.