Plugin Using AAR with Unity Free Getting DLLNotFoundException

I'm trying to write a plugin to utilize native code from One by AOL Mobile (formerly mMedia). I have a file from them that is an aar file. I have placed it in the Asset/Plugin/ folder.

My code right now is very simple.

[DllImport("mm-ad-sdk")] private static extern void initialize (Object obj);

void Start () { //initialize MMSDK initialize(this);
}

When I run the program in the editor I get an error "DllNotFoundException: mm-ad-sdk". I've tried to find the answer to my problem but been unable to find something that actually matches my issue and solves it.

Some additional information that may help. I'm using the free addition of Unity; however, I've seen posts that say after version 5.0 the free version can handle creating native plugins. Also the aar file also links to another aar file; however, since I'm not directly using that file I don't have call for DLLImport. I'm assuming this might cause a future issue that I will need to result, but wouldn't think it would cause the program not to find the aar file.

Any help would be appreciated.