The situation with Dying Light
has improved slightly.
2 of the missing DLC's are now available for purchase here on GOG: The Godfather Bundle
and the Rais Elite Bundle
We're however still missing 2 DLC's of in game content:
Left 4 Dead 2 Weapon Pack (Free on Steam) - Released 24th Oct 2019
Harran Inmate Bundle - Priced 2.39€ - Released 26th Nov 2019