The missing letter is:
The letters along the main diagonal are the initial letters of the 25 official James Bond films to date, starting Dr. No, From Russia With Love, Goldfinger, Thunderball... and finishing (at present) Quantum of Solace, Skyfall, Spectre... revealing our last one to be No Time to Die.
All other letters in the grid can be ignored.
There are a few clues dotted about to help point us in this direction:
The title is a reference to the 1981 Bond film For Your Eyes Only, and there are several '0' characters in the grid, possibly referring to Bond's pseudonymous codename '007' (double-oh seven); there is also (pleasingly) an occurrence of two consecutive 'O' characters in row 7!
The hints provided make additional references to the spy movie genre and the plot of Moonraker (1979) - the one film in which Bond goes to space - and the list of birds is a reference to the book Birds of the West Indies written by the real-life ornithologist James Bond, and on the bookshelf of author Ian Fleming, providing him with inspiration for the name!
EDIT: To acknowledge the OP's intention behind the hint "Someone witnessed this drama one day. The next day ended with a drama for this person." (revealed in comments):
As per the IMDB 'Trivia' page for From Russia With Love (1963), there's an interesting connection between this film and President John F. Kennedy:
Then-President John F. Kennedy listed Ian Fleming's book as among his top ten favorite novels of all time. That list was published in Life Magazine on March 17, 1961. Possibly as a result, the producers decided to make this the second James Bond movie. According to the book "Death of a President" (1964) by William Raymond Manchester, this was the last movie J.F.K. ever saw, in a private screening in the White House, November 20, 1963.
Kennedy was assassinated just two days later on November 22.