problems with DDL returned for dynamic vdb with google spreadsheet source

I am seeing inconsistent DDL returned for dynamic VDB with a google spreadsheet source. In the same google account, I created two spreadsheets. One was created in firefox browser, one was created in chrome browser (don't know why that matters)

See the attached document showing a comparison of the dynamic VDBs and the DDL that I got back. The only difference is that the source was pointing to a different spreadsheet.

Notice that the DDL for the "ChromeSheet" returns the concatenated datavalues for the column name. But it includes a NIS OPTION for the column name.