How to get the value of a parameter in a family table instance with VBA?

I have an Excel sheet that lists all of an assembly's components, and a "Part Number" parameter for each component. My problem is, the parameter isn't read if the component is a sub-assembly, or a part that is an instance of a family table.

Does anyone have an example of how to check if the component is a subassembly or FT instance, and if so...how to get a parameter value from it?

Here is a code snippet of how I'm reading the parameter from every componet (which works if its a part)

    For iCnt = 0 To (pathArray.Count - 1)

            Set eachPath = pathArray.item(iCnt + 1)

            Set mdl = eachPath.Leaf

            ' if model is part

            If mdl.Type = EpfcModelType.EpfcMDL_PART Then

                  iRow = iRow + 1

                  Range("Components").Cells(iRow, colFileName).Value = mdl.Filename

                  Set paramOwner = mdl

                  Set params = paramOwner.ListParams()

                  For i = 1 To (params.Count - 1)

                          ' Get part number and extrusion

                          Set param = params(i)

                          Set paramValue = param.Value

                          Set paramName = param

                          If paramName.Name = "PART_NUMBER" Then

                                  PartNumber = paramValue.StringValue

                                  Range("Components").Cells(iRow, colPartNumber).Value = PartNumber

                                  Exit For

                          End If

                   Next i

               End If

            End If

    Next iCnt