I have seen that video before, but never noticed that the caravan seemed to hold together quie well. In most of the disasters I have seen , the caravan has virtually exploded. Even so, stability control is a very important issue (and I don't have it!)

Basics.

Car loaded and level.
Van loaded and level,

and both ball and tongue parallel to each other, and the ground.

The Ball weight will then drop the centre of rig slightly.

The H.R (adjusting chains to suit.)
then brings it back up to level, or near.
Transferring some weight to front wheels.
Plus helping the sway too.

Preferably the van has suspension system set to rear of centre of van.
That gives a thousand times more stability than centre axle set suspension believe me.
Specially when it starts to swing. Which they ALL do at one time or another.

Also the tug should be a minimum of (myself 1/2 ton) 400kg
MORE basic road weight than the trailer.
The more. The safer it is for control of trailer. REGARDLESS of engine power.

Generators etc are a lot better IN rear of tug rather than hanging off front or rear of van.
But weight/balance permitting. On the front, rather than rear of van.

Remember water tank's loading too. Full and empty. specially with position of tanks
In front or rear of axles. Can make a huge difference.

I carried 300 ltrs (KG's) when they full. ALWAYS travelled with them empty.
Just a small 25ltr Stainless one for drinking.

That kept me around 5.7/5.8 ton combined with a 6.3 ton max allowed.
That incl, Tinny, Outboard. genny, welder etc.

And ALWAYS test your manual lever on brake controller.
Every time you couple up. BEFORE getting into traffic.
Just in case hey.