Rob,
Since changing the height of the WD jacks did not cause any changes in the deflections of the TV's front and rear (up 1/2" in the front and down 3/4" in the rear), it is reasonable to conclude that raising the weight distribution jacks did not cause too much weight to be removed from the rear axle.
This leaves two other possibilities to consider:
1) the sway you experienced was caused by raising the jacks -- but, via some other mechanism, or
2) the sway you experienced had nothing to do with the raising of the jacks.
In consideration of 1), it would be good to hitch the trailer and raise the jacks is several steps while checking the condition of the hitch and receiver at each jack height.
A close up photo of receiver, hitch, and bars at each step might be informative.
In consideration of 2), have you followed the recommendation of BarneyS to check the frame bracket assembly which controls lateral movement of the rear end of the yoke?
Also, have you checked the connections at the front of the yoke, and have you checked the ball and coupler for any looseness?
Good luck with your search for the cause of this sway.
Please keep us posted on what you find.
Ron