Three of PSG's South American stars – Edinson Cavani, Marquinhos and Angel Di Maria – have been granted extended leave alongside Marco Verratti and are due to return to training in Paris on Monday.
But Neymar, who was given permission to leave early before the mid-season break by Tuchel, and captain Thiago Silva are in contention for the game against Pontivy of the Championnat National 3 in Lorient.
"Yes, the South Americans will be well back. We said a lot about them, that [all] the South Americans arrive on January 7, but no, it's wrong," Tuchel told a pre-match news conference.
"It is the case for Edinson Cavani, but it was a negotiation between him and me, just like Marquinhos, it's my decision.
"With Di Maria and Verratti it's different. They have family and private things that will make them also arrive on January 7. These are the only four to come back later.
"Thiago Silva could have arrived later but I talked to him about the need for him to come back sooner because he's my captain and it was not a problem for him to come back on January 4.
"Finally, Neymar was gone before the others, so we agreed to come back on January 4."
Tuchel conceded he is a little in the dark over what to expect against Pontivy, who have only been beaten once since starting this season with back-to-back losses and are undefeated in eight outings across all competitions.
"It's very difficult to prepare for this kind of game. They haven't played since the draw was made. It's difficult to find video of Pontivy," the former Borussia Dortmund boss added.
"We're favourites and we want to win. It's not just another game. I expect of the players that they play with intensity and rigour to reach the next round."