Just closing this off after some interactions offline with the Mike...
This issue seems to be resolved now with some of the logic sorted out. The Labels macro now set to take some inputs passed in from the userform.
Code:
'Call the Labels function with some inputs
Labels sTo:=Me.cbTo.Column(3), sFrom:=Me.cbFrom.Column(3), iRow:=Me.cbRow
Function Labels(sTo As String, sFrom As String, iRow As Integer)
Dim aSheet As Worksheet, aRng As Range
Set aSheet = ActiveWorkbook.Sheets("Outer Envelope")
aSheet.Range("A1:B7").ClearContents
Set aRng = aSheet.Range("A" & iRow)
aRng.Value = sTo
aRng.Offset(0, 1).Value = sFrom
End Function