I don't see anything that might suggest this.
The statement
“lift assist tailboom design” implies that the tail assists with lift.
The canted tail-rotor has been used before. It adds a lift vector to the tail rotor, and the most recent use is Sikorsky's Comanche,
The Bell 525 appears to have a large lengthwise area for payload (passengers and cargo). A horizontal stabilizer with adjustable pitch would allow a slight longitudinal change in the craft's center of lift to suit a variabe center of gravity.
Just speculation. :noidea:
Dave