Mayybe i created that world one snapshot earlier. I am not sure anymore.
And additionally, all of the trapdoors and also the waxed copper grate are waterlogged. (screenshot) probably all blocks, that are waterloggable are waterlogged where the watercave should be.
I tried to recreate this issue in the versions 24w13a 24w12a 24w11a and 24w14potato. I wasnt able to recreate the exact same situation, but in the potato snapshot, the cave spiter spawner also generated insite of the trail chamber (the trail chamber generated a bit different wit the rooms).