They discovered a Ornithomimus fossil with feather impressions that showed it had full advanced wings, like deinonychosaurs did. Just like all deinonychosaurs they had primary feathers, which means that they attached to the second finger.
Did you actually read the publication itself? In fact they discovered an Ornithomimus fossil with carbonized traces of which could be the evidence of shafted feathers on the ulna and radius. Their distribution and orientation are similar to the insertion pattern of covert feathers. They suggest that adult Ornithomimus had feathers on its forearm with rigid shafts. While juveniles had "filamentous feathers" without rigid shaft. So there's nothing about full advanced wings, the lenght of feathers and primary or secondary feathers.
Evidence of advanced wings is only present in Maniraptora, and even then only in more derived forms (Therizinosaurs and Alvarezsaurs have feather impressions, but no complex wing feathers preserved yet). The only non-Maniraptoran Maniraptoriformes are Ornithomimosaurs, and no other Ornithomimosaur has evidence of advanced wings. Since there is no evidence of wings in more primitive groups, and only evidence of wings in more derived groups, it is safe to say that Ornithomimosaurs did not have advanced wings.