I wonder whether there is really a spot available for a 1-year graduate transfer? I think fans wish there were a spot available, but there is still that issue of Johnnie Vassar hanging out there:
https://northwestern.forums.rivals.com/threads/johnnie-vassar.31856/
Johnnie Vassar signed with NU but has never played, presumably because coaches came to realize he was not a good enough player to compete at high major level/B1G level as a scholarship player. Northwestern converted his scholarship to an academic scholarship, but I thought there was some question in regards to whether Northwestern could really do that AND not have Vassar count against the 13 allowed scholarships. My understanding is that staff, at various points, treated it like Vassar was not on a basketball scholarship but just did not get around to filling it. In the end, Northwestern may be lucky that it did not fill Vassar's position; because the conference 4-year scholarship guarantee may mean Vassar should have kept the spot even though he was not participating with the team. I think there was a thought process that Vassar would transfer. Instead, Vassar hung around on the academic scholarship and did not transfer for whatever reason (lack of effort?, lack of interest on his part?, lack of interested schools?, etc.) that maybe will come to light from his legal action against the university.
Johnnie Vassar's 4-years are up with the 2017-18 season, so any ambiguity about the scholarship being available would be eliminated for the 2018-19 season and beyond. At the same time, I looked at a lot of lists of available transfers and think it is slim pickings at this point in time for someone who is just in for a one-year graduate transfer situation who also likely meets NU's admissions requirements.
From a coaching/administration perspective; I would just let that spot be kept open just to be on the safe side compliance-wise, especially with that Vassar v NU lawsuit hanging out there. If someone were needed just to get to a 15-man roster, Northwestern could just open up competition to the student body for a third walk on for the upcoming season.