Wolfeels are more "fishlike" than eels, for lack of a better term, and you probably won't be able to scoop them into whatever you're using as you might be able to with a ribbon eel. I would just suggest sticking a piece of food into a net, letting it swim in, and lifting it out. They're very quick, and have good control over the entirety of their body, so you might want to cover the top of then net up right away, as it will easily slide out (as you have already experienced). Or, you could just stick a piece of capped pvc in there, stick in some food in the end, and when it swims in, pull the whole thing out, covering it up. Use a piece small enough that it won't be able to turn around, but big enough so that it doesn't injure itself when it starts thrashing around in the tube.