Have the dealer get the latest fluid chart from Ford. I'm going through a similar issue. The TSB is for cars built on or before 8-15-2011. Mine build date is 8-17-2011. I'm waiting for the Service Manager to get in touch with Ford Corporate about them paying for the work.
He also had not heard of the XL-18 additive. I asked him to pull up the fluid chart (should be from June 2013). For the MT-82 it has "see note 6". Note 6 below the chart states to add 27ml of XL-18 to any full fluid change. The chart for reference can be downloaded here: https://www.fcsdchemicalsandlubrican...f/mantrans.pdf