From what I read on the mixer, there may be a setting in the mixer itself to state what the USB output is going to cover. Inputs available should be listed across the top. If you see multiple colums, you then need to add either a mono or stereo input at the bottom of the matrix. So the left column will show numbers of each input you add, and that is how you will see them in the daw.
So bottom line, if you see inputs listed along the top of the matrix, then they are there and need to be added as stated above.
FYI, in the tool bar above the text entry screen here, there is a picture button that will allow you to upload a picture. As another FYI, no need to start new questions on the same issue, you can keep it to the same original question.