The most obvious omission is that you have made no attempt to open any DOCX format file. You macro is looking for TXT format files? I didn't bother looking past that.
It is not possible to help further without knowing how the 35 documents are formatted. You have already indicated that some of the documents don't contain all the data, so to enable disparate documents to be processed it is essential to know EXACTLY what we are dealing with. In which columns do you want to insert which data?