I think I got an answer. According to Microsoft's Query Table documentation
If you import data using the user interface, data from a Web query or a text query is imported as a QueryTable object, while all other external data is imported as a ListObject object.
I can't access QueryTable from the ODBCConnection object - however - a ListObject can be accessed from the Worksheet, that ListObject contains QueryTable, which in turn contains the Parameters object containing a list of all Parameters
ActiveWorkbook.Worksheets("Sheet1").ListObjects(1).QueryTable.Parameters
parameter SourceRange will return a Range (if the Parameter type is xlRange) - setting or changing the SourceRange however is done by setting the whole Parameter again:
param.SetParam xlRange, Workbooks(1).Worksheets(1).Range("A1")