Last week while spraying my Bermuda Lawn for weeds I inadvertently sprayed one patch of grass (200' x 12') with a herbicide (8.0% Glyphosate, 1.5% Oxyfluorfen, 0.1% Diquat). Well, it obviously did a great job killing the weeds, but it also killed this large patch of grass. I know that this is also in the soil and will probably prevent seeds from germinating for at least a month, but I wanted to know if it would be beneficial for me to bring in a couple of inches of new dirt and lay on top of the old "dead" sod and re-seed now?

Inadvertently you sprayed a 200 foot by 12 foot area? That's some power sprayer you got! Do you know you are talking about around 25 or 30 tons of dirt, about a big dump truck full? That would take near a month to spread out and till in. Your best bet would be either be patient and wait awhile or find a guy with a moldboard plow who can turn the old sod under--plow it under for you then you can disc it or rototill to get a good smooth surface you can seed on. Rototilling alone won't bury your dead sod deep enough, just mix it around.