There are two texture files for the Warden that don't appear to be used or are not loading. These are “warden_pulsating_spots_1” and “warden_pulsating_spots_2”.
Assuming that the attached images are in order, the first is of a Warden seen with Night Vision, and the second is of a Warden seen without Night Vision. The aforementioned textures are not visible in either.
The next three are images taken from the Minecraft Wiki. The first two DO have the textures visible, but are recreations and as such are not seen in game, and the last one is the default image of the Warden, where the textures are again not visible.
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