When using this particular question type, SquizMatrix v4.14.4 generates invalid markup:
... <tr> <th class="sq-backend-table-header" scope="col"></td> <th class="sq-backend-table-header" scope="col">Strongly disagree</th> <th class="sq-backend-table-header" scope="col">Disagree</th> <th class="sq-backend-table-header" scope="col">Neutral</th> <th class="sq-backend-table-header" scope="col">Agree</th> <th class="sq-backend-table-header" scope="col">Strongly Agree</th> </tr> ...
Note the first column's <th> is incorrectly closed as </td> (this defect repeats in subsequent rows), which invalidates xhtml produced and breaks XSL applied.
Is there a way to circumvent this somehow? Perhaps a smart ^replace::, but I'm not familiar enough with the squiz-supported regular expressions subset.