To answer most of the questions from above:

The cost of the business class from YYZ-CEB (return) is under $3,400USD all in.

They did mention that a change would cost $250 USD and that it is subject to price differences, which sounds like standard stuff to me.

I have no previous relationship with the Travel Agent

However, I am worried now that it appears the TA is selling a U-fare code award ticket.