Try Revolver. While Grama Grass is not listed on the label as a controlled weed many of it's cousins in Same Genus are.
An other way I would try first is Roundup. Bermuda is very tolerant of Roundup and will only show signs of stress for a short period of time. Since I am in South Florida Bermuda Never goes dormant. I spray Roundup in the Height of growing season and have not lost a yard yet.
it is one thing to do a off label applications. It is total stupidity to post it on the world wide web and expect people to approve.
You can lead a Donkey to water but you can't make the Jackass Drink