Here is a quick and dirty method to add the TC fields. It is somewhat flawed in using Selection objects because I can't immediately see why range won't work and couldn't be bothered figuring it out. You will have problems if there are instances of MyStyle spanning multiple paragraphs.
Code:
Sub aaa()
Dim aFN As Footnote, aRng As Range, aRngRef As Range, sCode As String, aFld As Field
Set aRng = Selection.Range.Sections(1).Range
With aRng.Find
.ClearFormatting
.Text = ""
.Style = "MyStyle"
Do While .Execute
sCode = "TC """ & aRng.Text & """ \l 1 "
aRng.Collapse wdCollapseEnd
Set aFld = ActiveDocument.Fields.Add(Range:=aRng, Text:=sCode)
aFld.Select
Selection.Font.Reset
aRng.Start = Selection.Range.End
aRng.End = aRng.Sections(1).Range.End
Loop
End With
End Sub