Gateway with Netezza and SharePoint List

Hello,

I have a report that's leveraging data from a Sharepoint list and Netezza. We already have a gateway configured for the Netezza source, so typically, I just select the gateway, apply it, and no credentials are required. With the sharepoint list, when I select the gateway for my netezza source, the "Apply" option is still greyed out.

I then try to check the credentials and for the Sharepoint List, I added the credentials and everything seems to be fine. However, adding my credentials to the netezza source does nothing and stays on the following screen:

Would anyone know how to configure the gateway for the netezza source when you have a sharepoint list? I dont have this issue when I have data from Netezza or just from Sharepoint, its when I have both, that I'm unable to set it up and without this, I can't refresh the data in my report. The two data sources aren't merged in Power Query or even linked in the data model 😞 

I'd really appreciate any help!