Question about Digital Potentiometers
The "absolute maximum ratings" table in the datasheet is the place to look. It indicates that Va, Vb, and Vw must all remain between 0V and Vdd. Since Vdd cannot exceed 8V, this chip will not work for you.

To see why, consider that - while the "pontentiometer" nodes may see only a small differential voltage - there are switches internal to the chip which span between the potentiometer nodes and the chips supply / ground. The voltage limitations of these switches is what prevents you from bringing the whole pot up to a higher common-mode voltage.

Fortunately, there are other digital pot products that should meet your needs!