Tosan got the same treatment but earned a Combine invite after his Elite Camp showing. Xaivian stated his intent to return barring a crazy offer, so I think it's all but certain now that he's coming back. Being a potential late 2nd rounder isn't worth leaving Princeton early.
It'll still be a great experience to meet with NBA teams and play against other top players. But the best way to boost that draft stock is with a monster junior year and NCAA tourney run. It would be amazing to see Lee stay for his senior year too, but I'm under no illusions in that department.