Worms. Big ol fat hand dug earth worms. They will catch big flatheads as easy as live gills.
Ain't no catfish can resist a glob of worms in muddy water. That's what they are feeding on when they are running the cut banks of a muddy creek. Have caught flatties in Denton creek up to 31 lbs on worms when it was running bank full muddy water.
Had an uncle that used mudcat and crawfish for bait and caught lots of huge channels in Caney north of Bonham when it was running full and muddy.
The key I think is to fish close to the bank. Throw lines with 3 to 5 hooks are good.
From Genesis: "And God promised men that good and obedient wives would be found in all corners of the earth."
Then He made the earth round...and He laughed and laughed and laughed!