Since you already have your hitch you could ad a sway arm for less than $75 and try that.
Being a windy day for your maiden voyage probably gave you a worse case senario, but it will get windy...."again" while your on the road. If you have sway, you have to STOP it, before it stops you. The problem being is when you get just that right frequincy from passing trucks and the sway becomes amplified, even more so than wind sometimes, and can lead to a sway of "no return". (Remember to lock up those trailer brakes if she starts getting wild back there).
The Armada is nearly at it's limit with a GVW trailer @ 8812 and the Armada at a towing capacity of 9100. Unfortunatley most manufactures over rate towing capacity.
Just remember the value of both vehicles, the persons inside, and the people around you on the road, not to mention your white nuckle experiences without sway control. RVW had the 1200lb equilzer for $450 bucks....WELL worth the money for the best you can buy. Equal-i-zer 4-Point Sway Control Trailer Hitch Introduction - YouTube