|3-3-6b: The base of support is below prep level or prep
That requires that one person (base or spotter) is in contact with the upper body AND in a position to protect the head, neck and shoulders of the top. The two on the side have both hands on her back, in a basket position. They are not in the type of contact that can protect the head, neck and shoulders, which we generally view as having one hand on each side of something they can grab. In addition, there’s a point when she’s upside down where they both remove contact. So, the two sides can’t count as being the person “in contact and in a position to protect the the h/n/s.”
There’s a person in the back who appears to be holding on to the ankle of the top. It appears that she also releases the top person in order to move into her next position. Even if she remained in contact, she’s holding the ankle, not the wrist or something that would count by rule as the upper body. Even if she changed her grip to grab the top person’s wrist, she’s not in a position to protect the top in case of a fall, with the position she’s in (basically behind the left side base.)
If it can be changed to where the bases on the side take one hand and grab the wrist of the top and basically make this a backward suspended roll, it could/would be legal. They would do that with their back hand, and with the front, they could basically “spot” the top up and over.
If something else is going on that I’ve missed because of the distance and angle of the video, let me know. But, by the current wording of the rule and what I can see, this is not legal as performed.