See, that's why warranties especially extended warranties are good to have

You have B2B protection still, right? Plus this would come under powertrain warranty, so again, no worries.
A drone is probably not the PTU, that would be more of a whine or a grinding if bad enough. Other symptoms are described in TSBs. I would suspect wheel bearings or tires TBH. If the sound is more prominent when turning one direction vs the other, wheel bearing. Try rotating the tires and see if it affects the sound. If it does, inspect the tires very carefully for cupping or other abnormal wear.
Ford did add a drain plug, temp sensor and cooling to the PP and PI PTU's. Nothing else of note that I have seen. It's worth checking the PTU fluid level & condition for sure, even if you don't R&R it. 10K seems a little early if you are driving the SHO moderately, but 25-30K, definitely.