Is this rigged model set up incorrectly or am I missing something to start the animation?

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I've run into a wall with this rigged and animated deer model from CGTrader. The fbx file seems to have imported correctly but the animation mixer does not affect the mesh. I've worked with the animation mixer before and am sure I'm starting the animation correctly, which leads me to believe it's a problem with the hierarchy. It's quite long but it has clips on the base layer so I'm not sure where the problem is... Any help would be greatly appreciated.

Pictures for reference: https://drive.google.com/drive/folders/147VIK4bBNApn5DLnpd0pg-9GXvNeEr-I?usp=sharing