After six players have been disqualified, Team A has only four who are eligible to continue in the game as players. In a gesture of fair play, the coach of Team B indicates a desire to withdraw a player so that each team will have four players on the court.
This is not permissible. Team B must have five players participating as long as it has that number available. If no substitute is available, a team must continue with fewer than five players. When only one player remains to participate, that team shall forfeit the game unless the referee believes this team still has an opportunity to win the game.