It seems the Excel COM object is missing and since TDM uses it for the export, you get the error. We have not tested Office 365 offline install yet, the last tested version is Office 2013, which works well.
ExcelApp = new ActiveXObject(“Excel.Application”);
If you get an error, the object is not available and it is not possible to use Export to Excel. The workaround is to use Export to CSV function instead, which is not dependent on anything else.