View model transformation with procedure as only source fails validation with The sql transformation does not have a valid source

I was following the Recursive Text E2E test. This calls for creating a relational source model with a procedure (getTextFiles) for use in a view model's transformation. With all this modeled, the transformation fails with the error: The sql transformation does not have a valid source.

The actual transformation SQL text is:
SELECT * FROM (EXEC text.getTextFiles('EmpData.txt')) AS f, TEXTTABLE(f.file COLUMNS lastName string, firstName string, middleName string, empId biginteger, department string, annualSalary double, title string, homePhone string, mgrId biginteger, street string, city string, state string, ZipCode string HEADER 3) AS emp

In previous versions this passed validation. Model project set is attached.