Several years ago I got skunked. On the 1 hour drive back home, I realized that all 5 places I had anchored were the same. They were all off points that I could anchor on the slope and hit the shallow water with some baits and the base of the slope in deep water as well as some baits staggered at various depths on the slope. I thought I had it all covered, but I got skunked. On the way home I realized I was fishing the same pattern, over and over. They could have been on the shallow flats. They could have been on the mussel shell beds, or in the back of creek fed coves, or chasing schools of threadfin suspended in deep water, or, or, or....
So, what I am saying is all your spots seem to be the same. River channel with sunken tree structure. You said you are fishing at night. The flatheads may be tight to the sunken trees during the day, but traveling looking for forage at night.
So my suggestion is: try the holes you suggested. But if they are not producing, try places outside the box. Try the shallow flat you marked in yellow. Where are you catching bait? Try fishing where the bait is; whether that is shallow or deep, in coves or in the main lake. The big catfish like to be where their food is. When I get to the lake to catch bait, I run up and down the lake looking for the diving seagulls, or I look for a bunch of boats congregated catching crappie or white perch. Then I go back and anchor for catfish in the same areas they were catching the perch or crappie. This time of year our big cats are getting ready to spawn and moving upriver to get stacked up with dams preventing them from going any further upriver. I anchor below the dams. When the wind is blowing, I will anchor on the far side bank because the bait will be blown that way and the cats will follow. During the winter, I may try the deeper water down river, because that is where I have had success. If there are bright lights on the bank or docks, I may trying anchoring on the edge of the light and the dark in the water. Etc, etc, etc.
Again, if you are not catching them where you would think they should be. Then try places that are totally different. You may get surprised.