Problem with the models

So I run a darkrp server, and I have a model problem.
The path to a model is: models/de_nuke/crate_small.mdl, we have put the model itself into garrysmod/models/de_nuke/crate_small.mdl and it still doesn’t work.
We put it under garrysmod/gamemodes/darkrp/content and still it doesn’t work.
All the files that come with the MDL (.vtx and so on) are in the folder too.
What am I doing wrong?

What do you mean by “doesn’t work”?