Diamond, who played Screech on the NBC sitcom, died Monday.
Josie Totah, whose credits include the Disney Channel's "Jessie," will appear alongside Mario Lopez and Elizabeth Berkley in the NBC revival.
"This is what 30+ years of friendship looks like," actor Mark-Paul Gosselaar wrote of the reunion dinner.
Saniyya Sidney told her “The Passage” co-star, who rose to fame on “Saved by the Bell,” that she only knows one "Zac" — Efron.
Zack and Kelly are getting together for "Dinner at Tiffani's."