Just wait a week and you are ready to go. These are contact post emergence herbicides and breakdown very quickly and do not prevent seed germination.

Since this is Bermuda grass, I wouldn't be so quick to assume it is dead yet, although 8% Glyphosate is very strong it may have done it in. I would water the heck out of it for a couple weeks before I would give it up as dead.

Also, if it is a hybrid bermuda lawn, you don't want to seed, as this type of turf cannot be seeded. The seeded varieties are lower quality and will not match the rest of your lawn. If you do have a hybrid bermuda lawn, I would buy a plugging tool and take some plugs out of your yard to plant in the killed area. The will fill in quickly to cover the area.

I agree with Tak. I've seen cluecless neighbors use common bermuda in hybrid bermuda lawn and it looks terrible...

I agree with the above and would add that any surrounding bermuda is not going to leave a bare spot for very long. Just leave it alone.