You have correctly identified the problem. I defined a shared datasource instead of local. Thank you for pointing it out.
Since it's not a shared datasource, I ran into another challenge. I cannot test the ErrorList by clicking the "!" button and have to use the preview tab instead. I now have a different error to debug. Something about [rsErrorReadingDataSetField] and [rsMissingFieldInDataSet]. I will work on this.
Again, thank you for your help. It will be a great tool for us when I get this working.