Validation rule VBS with LOV condition instead of identifier

Summary:

Hi team,
I am configuring a validation rule in Visual Builder Studio for an HCM Redwood page (specifically the Change Assignment flow).
In this flow, the Department field is a LOV.
When inspecting the field and when creating a Business Rule, I notice that the LOV only exposes the identifier (DepartmentId) as the field value.
The actual Department name / display label is not available in “Field Values,” nor in Advanced Expression or Code.

Because of this, I can only write validation conditions like:

$fields.employmentAssignments.DepartmentId.$numberValue() === <ID>

However, I need to validate based on the Department name (and specifically exclude any department whose name starts with a number, rather than validating on a specific name).