Vehicle tow ratings are for suckers. Those ratings are used by vehicle and travel trailer manufacturers to sell their stuff.
The tow vehicle's basic load rating will be exceeded way before you reach those tow ratings.
There should be a yellow sticker on the driver side door jamb. On that you'll see the vehicle's load capacity. A trailer needs 13% of it's weight to be on the ball. Figure about 7000 pounds for the Bronco and trailer. 13% of that is 910 pounds. Add the weight of a tank of fuel, passengers, and cargo.
You're overloaded.
If you flat tow it, you'll eliminate the tongue weight.
There is so much wrong in that, I am not sure where to even start.
Yes, there is a weight rating placard on the door jam, that part is correct.
The rest of that, not so much. I have been dealing with OEM certification of SAE J2807 (trailer tow standards) since before they were official. One of the members of the SAE board that deals with that standard happens to be sitting about 20 feet away from me at the moment, and I have worked with him on this stuff since at least 2002. It can be splitting hairs, but if they publish a tow rating, it has to be a towable configuration. Probably going to need a weight distributing hitch, especially the shorter wheelbase version of the Yukon. If you think those numbers are there only for sales, wrong. Sales wants the higher number so they can be the better towing vehicle, but there is science and testing to back up the claims. Not just a marketing guy pulling a number out of the air.
With that said, if you are trying to tow 7k with a truck only rated for 7k, it is often very difficult to accurately set up the trailer inside all the limitations. Sometimes it is easy, when the chassis has plenty of capacity but the limitation is the powertrain. But that Yukon isn't power limited. I remember them being very chassis limited. You are dancing with overloading the axle weight ratings.