I too have a 2013; i bought this on Amazon:
Kent-Moore EL-50448 TPMS Tire Pressure Monitor Sensor Activation Tool
i believe it is required. Instructions are in the Escalade manual. There are lots of others to choose from. This one worked for me.
I used it b/c the tire guys who put new tires on for me goofed up the programming, reversing the rear wheels.
Takes about two minutes.