Hi,
That's my bad, I missed the last screenshot of your message somehow.
In that case, the field is actually displaying on the listing.
However, we introduced a while back the "columns" switcher on the top right corner of the listing, which allows you to activate and deactivate the display of each columns of listings in the backend. I can see on your screenshot that only 10 columns are displayed out of the 18 columns available. I suppose that your tracking number column is one of the deactivated columns in there.