Apparently the only ones not able to rip off the Ontario Gov't are the tax payers. If the Gov't scrutinized their contractors the same way they do the rate payers, things like this wouldn't happen.
There is a significant history of 'Pay to play' with the Governing Liberals of Ontario... CN and CP representatives have probably attended fund raising functions. Heck, some Gov't unions are suing the Libs for selling part of Hydro One to their friends in a scheme to kick back money to the party.
One wonders if this over-billing was something to which a blind eye was turned...