We used to have WRs without Division 1 speed who nonetheless made plays for us. From Shaun Feldieson, who came as a walk-on Punter and ended up as a starting possession-type WR, to walk on Sparks (from either Plainfield or Plainville IIRC) who went over the middle and went low, but who had a role and again IIRC caught a TD pass in the Motor City Bowl. Donaldson may be that type of playr -- not having Division 1 measurables but having enough skills that he can fill a roll at WR if not be an every down player. Or a good enough FB player, if a step slow, to have a role on specials.