Hello, greetings from central Kentucky and welcome to the forum.
I pull our 23' Safari with a 2004 4Runner SE which has the 4.7 L V8 and full time 4WD. Tongue capacity is the same, 700 lbs. and towing capacity is 7,000 lbs. The AS owners manual says the dry weight of the AS tongue is 600 lbs. However, using my tongue scale, with stuff we always keep in the AS and 1 bottle of propane full, I find that the weight is 730 lbs. So actual tongue weight is higher when you have your gear in it. Your WD hitch will move some of the weight onto the front wheels and the AS wheels.
I use an Equalizer hitch and have been pulling it since 2014 without any problems, the rig is very steady and easy to pull the AS. I've had a couple of panic situations (people suddenly coming into my lane) and the 4Runner did quite well. You should be fine.