As it can be seen on the Denodo Connects page in the Denodo OData 2 Custom Wrapper description, OData Version 3.0 is only partially supported by this wrapper. I would make sure that Denodo is updated to the latest version and the latest Denodo OData 2 Custom Wrapper (20180329) is being used. I would also make sure if the OData version of sharepoint hasn’t changed. You can find ways to connect to Share point in [this](https://community.denodo.com/kb/view/document/Microsoft%20SharePoint%20as%20data%20source?category=Data+Sources) document.
If you are a Denodo Customer, you can probably open a support case regarding this problem.
Hope this helps!