Joe1 asks all the right questions, thus I'll give you my blunt thoughts.
If this is the first time your boyfriend has pulled a trailer with any significant load, then he'll wreck before he gets home. If he has some trailer pulling experience and can back up a trailer, he has a chance.
IMHO, the only way that this can have a successful outcome with adequate safety is that the trailer be a gooseneck, have adjustable brakes that work, maintain speeds under 50MPH at all times, your boyfriend must carefully plan ahead his speed both up and down hills, slow to a stop well ahead of where you MUST stop, no panic stops, plan ahead before you pull into a parking spot or around a corner so you have an adequate exit path.
From your description, things are on the very edge of a problem. The pickup is light. Hopefully it has a very big engine. The tow weight is rather heavy.
Fundamentally, either your boyfriend has good judgement or not in how to drive. That can't be taught.. but is critical to a successful outcome.
If you answer fully all the questions that Joe1 asked, then I am sure that other TBN members will provide their opinions as well.
I HAVE done what your boyfriend is planning.. and survived.
In my case it was 5500 pounds of live cattle with a bumper hitch 1/2 ton underpowered pickup, no trailer brakes but on mostly level ground, for 250 miles. White knuckles all the way. And, I already had lots of experience hauling with lighter loads and/or better gear. I have twice had a trailer start whipping around on me... and done a 360 circle on the highway... thankfully, somehow, didn't turn over... you can't believe how fast it happens!
I wish you both the very best and a safe trip with good weather!
The best advice I can give is to approach this effort with extreme respect for what can happen and use constant and extreme care during the drive. Usually it takes 3 simultaneous problems for an accident to occur. Speed control and anticipatory/defensive driving are the factors that remain under your control after the tow vehicle, trailer and load are all selected, loaded, chained down, and mechanically ready for the trip. Be ready to change tires!