SSAS server list is empty using Ent Gateway

Hi

We have configured Ent Gateway link

But SSAS server list is empty  link

perhaps SSAS source is in another place..

And the second question - If I am right, we can use two ways to publish SSAS data to PowerBI web site:

- Using gateway 

- Using PowerBI Desktop (to create PBIX file with conection to SSAS ) and OneDrive (put here PBIX file). Then open in PowerBI Site OneDrive source this file.

Both this ways allow using SSAS with PowerBI and always get current data with high speed. Am I right in this?