Just follow the price action and don't overthink it. My FA take is that they are not necessarily trading together. With inflation going up, Oil service does face increasing pressure in terms of cost while USO is a pure commodity play.
While DCR (2x short oil) set another new low, DUG had a reversal day on huge volume and closed in the green. Let's see whether the oil stocks continue the fall tomorrow before declaring that oil itself will start sliding soon.