According to Calvin Watkins of the Dallas Morning News, Lee is expected to re-sign with the Cowboys but Witten "not so much."
Lee has spent his entire 10-year career in Dallas, and Witten was with the Cowboys for 15 seasons from 2003-17 before retiring. Witten spent 2018 as an announcer for ESPN's Monday Night Football, but he returned to start all 16 games for Dallas last season.
The 33-year-old Lee was a second-round pick of the Cowboys in 2010 out of Penn State, and while he has been a highly productive player when healthy, injuries have been an issue.
Last season marked the first time Lee ever appeared in all 16 games, and he has missed five or more contests in a campaign on five occasions, including in 2014, which he sat out with a torn ACL.
Despite his durability concerns, Lee is a two-time Pro Bowler and one-time first-team All-Pro who has reached the 100-tackle mark four times.
In 2019, Lee made 13 starts and finished with 86 tackles, four passes defended, one interception and one sack.
If Lee does return to the Cowboys in 2020, it will likely be as the starting weak-side linebacker alongside Jaylon Smith and Leighton Vander Esch. Lee is also capable of sliding inside when need be, as he spent much of his career at middle linebacker.
Witten is one of the greatest tight ends of all time and a surefire Hall of Famer, but the 37-year-old veteran is essentially just a station-to-station guy who can keep the chains moving with his great hands at this point.
While Witten set a career low last season with 8.4 yards per catch, he was fairly productive as a safety valve for quarterback Dak Prescott, recording 63 receptions for 529 yards and four touchdowns.
Witten has impressively missed just one game—during his rookie year—throughout his 16-year career.
The 11-time Pro Bowler and two-time first-team All-Pro is fourth on the NFL's all-time receptions list with 1,215, and his 12,977 career receiving yards are 19th in league history, second to only Tony Gonzalez among tight ends.
Witten can still be a useful player, especially in short-yardage situations and in the red zone, but letting him walk would allow tight ends Blake Jarwin and Dalton Schultz to play bigger roles next season.
Jarwin flashed big-time potential in 2018 with 27 catches for 307 yards and three touchdowns, and he took a slight step forward last season even with Witten in the fold, registering 31 grabs for 365 yards and three scores.
Schultz had just one reception last season, but he was a fourth-round pick out of Stanford in 2018 and has some untapped potential.
If the Cowboys don't re-sign Witten, it is unclear if that means he will retire again or look elsewhere for work. It is tough to envision him in another uniform, but the NFC East rival New York Giants could be a landing spot since they hired longtime Dallas head coach Jason Garrett as their offensive coordinator this offseason.