[2023] Toxoids not showing in game

If it is in our launcher it really has to be in the game too. Toxoids requires at least patch 3.5, are you on that or something later? Current is 3.8.4

When you go into New Game or MP from the main game menu, DLCs are listed on the right of the screen. Is Toxoids there and ticked?  

If you had opted into a beta of an older version, that tells Steam you don't want to update.