OK, there are 3 different ways to generate rotation (spin)
1- "Contact twist", the most common in newschool skiing; when rotation is set on take-off (contact with the ground is used in the set)
2- "Tilt twist", think traditional aerials: this is when weight is changed on a flipping body to create spin. This is how aerialists can do tricks like a "lay-tuck-full" with no rotation on the first two flips and then a 360 on the final flip. (Using tilt twist it is actually physically possible to do a flip with a spin to the right, un-tilt, then do another flip with a spin to the left.) Tilt twist only works on a body that is already rotating on a flipping axis.
3- "Cat twist", sometimes known as hula hoop twist; the most awkward form of rotating involves basically flailing the body around in segments, upper-lower-upper-lower (cat out the window actually does apply here)
So anyways, it looks like what Pep did was a very slight "contact twist" to the left on take-off, but countered and overcame it with a whole lot of "cat twist" to the right once in the air.