You are well below the max tow weight IF you don't load the trailer too much. You will need to travel light.
The hitch weight looks ok, but it will be higher with a battery and full propane tank. Thats OK.
The main thing you are going to run out of is cargo capacity on your Highlander. The hitch weight of the trailer is part of the cargo. Check the Highlander max loaded weight.
You are going to know that trailer is back there for sure. Shift down going up or down grades. Get in the right lane and stay there. Don't get in a rush. The single biggest safety issue is STOPPING the trailer, not pulling it. You MUST have a good brake controller set up correctly, and a good sway bar. You need to get used to travelling on fairly level routes before doing big hills and mountains.