There have been times, especially when the MK bus stops were being upgraded, that the WL bus has gone to the TTC rather than straight to MK. But as of right now, I do not think any buses from WL would even stop at the TTC.
As other posters have mentioned, using the TTC as a transport hub isn't really as easy now as it used to be, when it really was more of a hub for buses as well as the monorail.
But, if you really have a yearning to see the TTC, you could hop on the boat from WL to MK, then get on the ferry or monorail from there to the TTC. If you want a scenic route to EPCOT, for instance, you could do this, and then get on the EPCOT monorail at the TTC. But by no means would this be anywhere near as fast or easy as simply getting on the EPCOT bus at WL.