"Cells" isn't global. It is a property of a Worksheet.
You should define a Worksheet variable (e.g. xlSheet) and set it to the ActiveSheet in the Workbook.
Something like set xlSheet = xlApp.ActiveWorkbook.ActiveSheet
Or Set xlBook = xlApp.Workbooks.Open(someXLfilename)
Set xlSheet = xlBook.Sheets(1)
Then you can use xlSheet.Cells
I suppose I used the wrong terminology to explain "Cells". I was meaning to refer to the need to include the Microsoft Excel Reference for "Cells" to work and how the API refers to it as a Member of the Excel.Global.
I figured out the issue, being that I was using a With xlWB.Worksheets("Sheet Example") statement and for whatever reason using a With statement doesn't work on the second excel file. So like Simon said above, as long as you define and use xlws.cells it will work.