Some PBI Datasets not showing in Excel

I'm working on a PoC to test using PBI Datasets within Excel (both Excel Desktop and Excel for the Web) and I'm getting mixed experiences that I can't isolate/resolve. Most datasets aren't available within Excel, but a couple are.

Here is my setup:

- Several Datasets deployed to PBI Service... most in "My Workspace" and a couple in a "Development" Workspace.

- I have Admin/All Permission access to all the Workspaces and Datasets (I'm also the Owner of all "Data Source" connections in the Gateway Portal).

- I'm currently on a Trial PBI Pro licence (to test creating Workspaces and sharing Datasets with others in my team).

- Here are the Datasets in my "Development" Workspace, none of these are available in Excel (Desktop or For The Web):

- Here are the Datasets in "My Workspace", only 2 of these appear in Excel for the Web, but none in the Excel Desktop:

- In Excel Desktop none of the datasets appear either via Insert -> Pivot Table -> From Power BI or via Data -> Get Data -> From Power Platform -> From Power BI (note: I'm signed in, our tenant name appears in brackets after "From Power BI" and I believe we meet the prerequisites listed here: https://learn.microsoft.com/en-us/power-bi/collaborate-share/service-connect-power-bi-datasets-excel)

- Via my OneDrive, I can open a new Excel Workbook and via Insert -> Pivot Table -> From Power BI there are 2 Datasets that are available, but none of the others (most importantly none from my "Development" Workspace:

- For all of these Datasets I can "Analyze in Excel" to open and connect to them in Excel for the Web.

Ideally, I would like our other developers to be able to open up excel and connnect to publilshed datasets they have access to. Is there something I have missed? Why would only 2 datasets be available, and not the rest, even though they appear to be setup the same?b

Kind regards

Scott