Whoa!!!
I scared myself under similar conditions. Downhill open desert south of Fernley Nevada with the modern highway descending at a uniform grade, in a straight line, through several highway cuts. I was pulling at small but tall camp trailer with an AMC Eagle, no brakes on the trailer. I came out of one of the hillside cuts and an unexpected crosswind nearly tossed me off the road. Gentle acceleration to make sure the trailer didn't get in front of me was enough to calm down the sway, but for a moment it had felt like the whole rig was going to be spun around backward. Nevada's Wind Warning billboards mean business!
I couldn't view the video, so many add re-directs and whatnot, kaspersky didn't like the site.
However, I can see what looks like went on with sway, etc from the static clickbait picture.
Do those big camper trailers not have electric brakes? If they do, and a sway or fishtail started, all the driver had to do was start using the trailer brakes ...
I remember back when I only pulled with a half ton or sometimes a 3/4 ton. Trying to get by right up to the edge of specs, legal but barely.
I remember one day coming home from working on the farm in my dodge ram with bumper pull trailer, had a tractor with hog and some other farm gear on the trailer, and some other stuff in the truck bed. Tounge weight was correct.. I was just right on the edge.. of everything.. weight, engine, combined braking ability on truck and trailer, etc.
So I'm making the last curve before getting into my neighborhood, turning off the highway onto a short stub connecting road, that would connect to the frontage road that accessed my neighborhood, another neighborhood, and 2 strip malls. speed limit went from 55 to 40 to 30. I was on the 40 section. ( just stubbed off the highway ).
Out of nowhere a small girl on her small training wheel pink colored bike ( 5-7ys old?? ) rides out from behind a green box on the side of the road, and right across the 40mph roadway section, never paused, stopped or looked..... and she was 20' in front of me... I had slowed to about 35 mph.. thankfully.... if I had been going 1 mph more maybee.. it would have been disaster.
So what does the kid do? she 'squirrels'. IE.. she road right out in front of me and slowed to try to stop in the middle of my travel lane! Slammed on brakes, steered hard right. That section on the right was not a ditch, but smooth, where the kid rode out from.. the rest of the area is ditch. By now, the kid has stopped in the middle of my lane, my truck is passing her on the right as I'm heading into the flat right of way... problem is I have another 20' of trailer behind me, so I have to maneuver the right of way, mailboxes, trees that are 15' from the road edge, etc, so that the trailer swings around the kid. I actually travel in about a 150' arc around the kid till I come to a stop having skidded thru the grass/dirt on the right of way, and back onto the road, passed the kid. At this point the kid is in the middle of the road in traffic!
I jump out of my truck to run back and check on the kid ( completely untouched by the way ), and she continues peddeling and zooms off right across the other lane of traffic, never looking at all.. ( thankfully the oncomming car was stopped because I had re-entered the road at an odd angle.) and rides up on the. grassy shoulder and another 100' or so, then i see her mother standing outside her house... mother starts yelling waving one of her hands in the direction of the traffic telling us we were all ' #1 " ...
IMHO.. bad parenting....
I bought a 1 ton dually that weekend... and then a real trailer.. not something that hooks to the bumper.