It looks like multiple schools of suspended fish.
On the next to the last picture, at the bottom right, those are suspended fish.
You can see the shadows to the right of the fish.
On the last picture, you have some type of channel or crevice on the left side of
the SI in the middle.
When you scan, keep your boat going in as straight a line as possible.
Also, match exactly your chart speed to your mph boat speed.