Getting a OneDrive Excel to refresh using gateway, when it's been setup as mashup in Desktop

Hi All,

I have followed this process to hook a mashup dataset in Power BI Desktop to an excel workbook stored in OneDrive:

https://docs.microsoft.com/en-us/power-bi/desktop-use-onedrive-business-links

However, i have now published my report to the Service, and want the report to refresh on schedule using our on-prem Gateway.

The other data sources for my report (SQL Server) are setup and working absolutely fine in the gateway, and have been refreshing regularly for weeks now, with no problem.

I can't, however, figure out how to setup the data source connection for the OneDrive excel workbook that's in the report. 

Given that the steps in the link above tell you to setup the data source as a 'web' source, i figured i'd have to set it up in the same way in the gateway, but i can't seem to get it to work.

Does anyone have a clue how this is supposed to work?

Many thanks.