...Could someone give me a code (if there is one) to make the headers transparent in only one column (the third)?

You can do it by what sections appear in that column.

{display: none;} {display: none;} {display: none;} {display: none;} {display: none;} {display: none;} {display: none;} {display: none;} {display: none;} {display: none;} {display: none;}