your model is designed with some very thin sections at the cutting edge and the shoulders between the bat's cheeks and it's wings
additionally you have scaled the model down, so the thin parts get even thinner
so the Slicer doesn't place any filament where the section is too thin.
in the top picture, you can see two spikes
these are caused because the two lines come together in the pointed areas circled in the second picture.
in the third picture you can just about see the two spikes in reality. where I test printed the model...
it's not the best print, I set it going, using the dregs of a reel of filament at 200% speed, to print quickly, then forgot to slow it down for the top part... but it clearly shows that the thin edge section and the shoulder parts didn't get realised because they are too thin