Nice big jump, Draft is apparently a super good kite for boosting!
The additional force beyond what you get from a idealized jump, keeping Jesse at a constant altitude force is most likely what is called convection - hot air below expands and due to a lower density than the surroundings and thereby it will start to move upwards in bubbles that can will grow into showers depending on the convection height and atmospheric conditions. A very common thing at Maui (rainbow island) shores. Another solution is mechanical turbulence, which is eddies created by obstacles, just like you get behind trees etc. This jump just does not look like that is the case.
This clip is legit to me since it shows the actual jump and in general the higher you can jump the more likely it is for you to catch thermal convection (winds going vertical).
Hanggliders can stay in the air for hours and hours in thermals...
at the same time this is not a lot different from the BS when kite companies claim that their kite can ride on glossy water in just 4-6 knots. The to this answer is simply that the wind packs above and at kite height there is a LOT more wind. The wind shear can be great when the water is really cool and some warm stable air is flowing in. Stable conditions is key!
This is pretty common in Europe during spring and I have experienced that myself many times. Sometimes the cold air below will even decouple from the upper wind, which means you can have 2 knots at the surface and 20 knots where the kite is at 25 metres..
still, its a nice jump and still it´s ok for Naish to put it in the video!
Thomas (Meteorologist dude with some knowledge about surface winds, wind shears etc. in relation to wind energy and kiting, working for Vestas full time as meteorologist and helping LF with R&D making gear like the HifiX that Nick Jacobsen just got his 2nd place in King of The Air on btw...)
Boosting is cool