Lee was injured early in the fourth quarter of a 59-49 loss to Richmond on Saturday - the No. 9 Dukes' first of the season - and the school said Monday that Lee would have an MRI on his foot.
Lee ranks first in the FCS in total offense at 375.5 yards per game and has accounted for 29 touchdowns (21 passing, eight rushing) in eight games.
He finishes his career tied for the school passing touchdown mark (51), is second in total offense (7,292 yards), third in passing yards (5,652) and completions (446), and fourth in pass attempts (705).
"If you are a JMU alum, fan, student or supporter and you have gotten to see this young man play in the last 21 games at JMU, you know you have witnessed something special," Withers said.
"Vad Lee will finish his career statistically as one of the best quarterbacks to play at JMU, but looking beyond just his impressive stats, Vad Lee was a game changer. He's not only one of the best players in JMU history, but one of the best people I have ever been associated with. Vad will continue to be the vocal leader of this team as we continue to fight for Madison down the stretch."
Schor rushed for his first career touchdown and threw for his first score in the fourth quarter against Richmond. He is 8 for 11 for 115 yards and has carried the ball 13 times for 57 yards this season.
"In the process of building a program, you're only as good as your two," Withers said. "That's been our mantra, we talk about strength in the unit in our programs. Everybody in our unit has a responsibility to prepare the same, just like a starter. So Bryan's done an unbelievable job of that. We've had people step up because of injury in the past."