The 24-year-old returned on loan to BVB in January after the breakdown of his relationship with Manchester United head coach Erik ten Hag.
Sancho helped the Bundesliga giants reach the Champions League final, and he played 87 minutes of his loan club's 2-0 defeat to Real Madrid in the English capital.
The forward, as it stands, will return to his parent club this summer, but Dortmund are believed to be determined to re-sign him on a permanent basis during the summer market.
Terzic has hailed Sancho for his "brilliant" form since returning to the club, but the BVB head coach could not offer any guarantees over a return to Signal Iduna Park.
Sancho is heading back to Old Trafford as it stands
"The last six months, Jadon has been brilliant for us. Of course, it took him some time to get back into shape. But you could feel his quality was going to help our game, his first touch. He improved himself and those around him," Terzic told reporters after the clash at Wembley.
"I didn't speak about the future because we've been speaking about the present. I am really happy that he is with us. Playing in a final in his hometown, it's a very special moment for him.
"You can feel the joy he receives and brings in the dressing room. I am very happy to work with Jadon. We don't know yet what the future will bring. But for sure, it's going to bring him another Champions League final."
Sancho scored three goals and registered three assists in 21 appearances for Dortmund after his switch back to the club during the winter transfer window.
The forward made three substitute outings for Man United in the opening stages of the 2023-24 campaign before his high-profile falling-out with Red Devils boss Ten Hag.
Sancho has a contract at Old Trafford until June 2026
Man United are believed to want as much as £50m for Sancho this summer, while the club are not thought to be willing to listen to offers of under £40m.
Dortmund's 2023-24 campaign will have boosted their funds for the summer market, but it remains to be seen whether they are able to agree a permanent deal for the ex-Manchester City youngster.
Across two spells, Sancho has managed 53 goals and 67 assists in 158 appearances for BVB, but he has only contributed 12 goals and six assists in 82 matches for Man United.
The attacker has another two years left to run on his deal at Old Trafford, and it is very difficult to imagine him playing under Ten Hag again.
However, a change of manager at Man United, with a final decision thought to be imminent, could potentially see Sancho return to the club for the 2024-25 campaign.