That’s my understanding as well. You need DC supply voltage on one pin and then a control voltage on the other. Hysteresis shouldn’t exist as there’s a displacement feedback in the valve controller.
Here’s some discussion & working setups in another thread .ino for PCB+MD13S+Danfoss valve You should see something like 25-75% of U_DC in U_S, check out the pictures towards the back of the thread from @Kaupoi and @Larsvest