The real question is whether there are other such situations. It's unlikely that other TA's would post here and this OP took some number of weeks to do so. He could be a single example or one of many in a widespread crackdown.

TA's are the easy targets because the ADM system makes cost recovery simple and because the TA relationship to BA is business-to-business.

One has to wonder whether BA caught some individuals and interviewed them and was told that they were told by their TA that they need not fly the last segment.