I have the latest Garuda Cinnamon with a fresh full install and I can not disable red shift on the Adwaita default theme wallpaper, all the windows display as normal just not the wallpaper. I have not been able to find any setting for it in the Cinnamon settings.
With Red shift enabled everything is tinted as it should but I have Red shift disabled and set to 6500k for day/night. With any other image this does not happen only with the Adwaita wallpaper.
This is day:
This is night: