can you explain why wind will affect them relative to each other? Aerodynamically the aircraft do not "know" there is any wind.
There are two differing discussions here:
If all of the planes are in the same formation, they
should experience the same air mass, and resultant effects. Wake turbulence could still be a factor, but generally the formation does not have a formed up plane well aft in the wake turbulence zone of a forward plane. If the formed up plane is in a wake turbulence zone, it would be more constant, than an "event". When sending off jumpers while in formation, the jumpers would be leaving the formation, thus transitioning to another air mass, and subject to the effects of wake turbulence of another aircraft in the jump run formation (though not from the airplane that they're jumping from).
In the case of the video, the airplanes were not in the same formation, the fast one made wake turbulence which was not a part of the formation collective air mass, which the wind would carry [into the path of the other slower plane].