Variable library usage leads to error with dynamic data destination

Hi,

I am trying to use a dataflow to load data from an external PostgreSQL database into a Lakehouse. I have dev, test, and prod workspaces created and linked through a deployment pipeline, with identical lakehouses in each. Therefore, as the dataflow goes from one workspace to the next, the destination needs to be managed accordingly (as it doesn't automatically update as part of the deployment process).

I have tried using a variable library (based on this documentation) that contains the Workspace and Lakehouse IDs for each stage, but run into an error.

I create the WorkspaceID variable using this query (with an equivalent one for the lakehouse ID), and disable staging:

This produces the expected value:

However, as soon as I add a table, I get the following error with the variables:

The import Variable.ValueOrDefault matches no exports. Did you miss a module reference?

Any help would be appreciated - thanks!