If it were mine, I would make a cut 0r 2 on the side of the trunk, and wrap wet paper towel and plastic loosely over the cut. Tie the towel and plastic on to keep the cut moist. Possibly you can encourage the trunk to sprout that way.
I have a large yucca like this that I winter indoors, and place outside under trees for the summer. It lost its top one year in a bad storm, and sent up more stems lower down a month or so later. It did not lose all its green leaves, though.
I can't even imagine shipping a yucca as large as yours! Nine foot, whew! Good luck!
