What version of the controller are you running? I would completely remove the asset and add it again - the Asset Store version compiles without any issues.
The problem isn't the integration files - it's that you are running a newer version of inventory than what is supported by the same shared files of the legacy version of the controller. Version 3 of the controller is a paid update:
Get the Third Person Controller package from Opsive and speed up your game development process. Find this & other Game Toolkits options on the Unity Asset Store.
assetstore.unity.com
I forgot what the error is but on the line that is giving you the error you can either add or remove a parameter in order to add compatibility with the legacy versions of the controller. From there I would not update the inventory asset anymore if you want to keep it in sync with the legacy version.