I've had a lifetime of recovery equipment experience. Right this minute i'm recovering from 10 days on business in Sweden and my recovery equipment is lots of black coffee. Just remember, you want the tow strap to be strong enough for the heaviest side of the tow as the strap must withstand the same load whether you are the tow-er or the tow-ee. Here's the short list for use with a 10,000 pound camper strap-towing anything or being strapped. You need to know that there is nothing more stuck than a truck camper down to the frame in sand or snow.
1. Several tow attachment points, fore and aft on your truck. Funny how this is the first thing you need to have before a successful tow strap use. I use the largest "D" ring that will fit in a H.D. receiver, no-drop, hitch ball hole as a truck rear attachment point. Nice pivot and easy on the strap. On most travels with the camper (if I'm not towing) this set-up remains in class V receiver on the rear of the truck.
2. 30,000 pound, 4" nylon tow strap with shielded loops. It may seem like overkill, but just think about the working load of trying to pull your stuck-to-the-frame camper out of a jam. Left over from my jeeping dayz, I carry another 3" strap with a lesser load rating. Sometimes, depending on the situation, I can loop the two through each other making a much longer tow strap, with the diminished load rating, of course. I also carry a "tree saver", a winch attachment strap with a very high working load. It's only five feet long, but extra stout. The technique is to find a suitable attachment location. On a passenger vehicle like your van, this is the most difficult prospect. So, you want lots of options on connecting hard parts. It may be possible to loop the strap over the frame or axle and back through itself to get a solid, safe connection. There are no bumpers anymore on passenger vehicles, so a frame or chassis connection is inevitable.
3. Several and various sized "D" rings (or clevis rings) with a high load rating. Mine are, Oh, 8K, 11K, and 15K pound rated. The downside is these are pretty heavy, but they fit many applications. These can be had at a large hardware store and have the load rating in tons, cast right on the loop.
4. I do carry a wide mouth, 12K pound rated hook with a spring loaded clasp with a 4" wide opening connected to yet another D ring for those impossible to connect situations. The key here is the clasp for safety. No clasp; no use.
4. A short piece of heavy chain with a clasped hook on one end and a slip hook on the other to wrap around axles, frame members, and any place on the tow-ee where "D" rings won't fit. It can be as short as 4 to 6 feet long. I know i will get flack for this, but occasionally it's the most appropriate way to connect to the tow. You wrap it around a couple times for lots of friction and a firm pull point, slipping the slip hook at the tightest link. The common woe here is there is no good place to connect to the civilian vehicle so you need lots of options.
5. As said above, keep you tow strap out of the sun. Over time it will degrade the working load.
6. A few years ago when my brother moved to rural Nevada City, the very large chassis moving van got his departure angle stuck coming up a steep pitch on his dirt driveway. Just one side of the 22" duals was spinning to no effect, tires jerking up and down. I connected my big strap to the front of the rig and pulled him right up (in 4WD, of course). He had no good attachment point on the front so I wrapped the chain around a frame member and connected the 4"strap to the wide hook/. It was a very large truck, but I felt safe using the tow savvy I've learned over the years.
This may be way more info than you need, but you never know when you will be called upon to tow something really big out of the way or to the nearest garage. BTDT.
regards, as always, jefe