Models show as errors unless I change directory

So, I have like a preview view for models to choose from, now if it's set to the original directory of the model "models/humans/modern/male_01_01.mdl" The models work fine but the preview shows an error.

If i change "models/humans/modern/male_01_01.mdl" so modern says something else, the models do NOT work fine but preview with no error.

Any ideas how I can sort this? So they work correctly