This video is slightly old but covers most of it. When it mentions about going to the VPP portal, this will be your Apple School Manager. It's a lot simpler than it sounds and the instructions on the page you listed are all there is to it.

https://www.youtube.com/watch?v=V3XtnEWJgZE

Thanks.

It looks like its now under User > Preferences > Your MDM Servers > Choose Server > Download Token

This part makes me leery, so I want to verify that's the correct place:

Thanks!

I don't think that's the correct one. You need the VPP token. Struggling to find where it is in this new interface.

Found it. It's under User > Preferences > Payments and Billing > Server Tokens > Download the server token you need. 

That was well hidden and it doesnt even look like a button.

JAMF needs to keep these token help files updated better.

Thanks for all your help!  You get a solution!