What does IMG explain? Why would Tennis Canada care? They run the Rogers Cup in order to make as much money as possible to support their operations for the rest of the year. So I understood WCs go to help Canadian tennis players or because they think it will help sell tickets. Where does IMG fit in?
To be honest, I haven't paid much attention to how Tennis Canada run this things, so I'm not saying it must be true. Though I get the feeling that Tennis Canada seem quite faithful to their own players, it's not implausible to think that ATP / a big management agency like IMG which have a great influence on ATP, may give a word on one WC in some ways. Of course, TC may simply have thought he could sell more tickets. Again, it's speculation, not a statement.