Dinwiddie first tested positive for the virus in June.
The 27-year-old is the latest Nets player to withdraw from the league's planned restart at Walt Disney World. Dinwiddie joins injured players Kevin Durant, Kyrie Irving, and Nicolas Claxton; veteran center DeAndre Jordan, who also tested positive for COVID-19; and veteran wing Wilson Chandler, who opted out of playing for the safety of his family.
With the current expected absences, Caris LeVert will enter the NBA's Orlando campus as the team's top active scorer and playmaker with 17.7 points and 4.1 assists per game.
The Nets enter the eight-game seeding phase ranked seventh in the Eastern Conference with a 30-34 record. Should the No. 8 Orlando Magic (30-35) pass Brooklyn in the standings, the ninth-seeded Washington Wizards (24-40) can trigger a double-elimination play-in round by finishing within four games of the Nets for the conference's final playoff berth. Brooklyn's first game back comes against the Magic on July 31.