Are they called redshirt juniors if they never redshirted? I think not but it's semantics - they would be eligible for the grad year.
This is not a difficult concept.
Each student athlete gets five academic years in which to exhaust 4 years of NCAA eligibility. A player in their 4th year of NCAA eligibility who does not redshirt is called a true senior. Following a true senior season, they have exhausted their NCAA eligibility. They do not get a "grad year."
Still with me?
Now, should a player graduate academically early (i.e. Emeka Okafor), but still have NCAA eligibility, they have the 3 choices listed above (four actually, but I'll keep it simple, in consideration for my audience.). Regardless, none of them include re-entering college after the draft.
This is the last time I will address this here, however I reserve my right to ridicule, mock, and scorn on each later occasion that I see fit (and make no mistake, I will take full advantage of that right), as should anyone else.