The short answer is that I can't speak for them. I don't know why they haven't acted. I do know that within days of the election approximately a year ago, Mr. Goodale was doing print interviews in which he supported the idea of an audit to find out what had happened, where the taxpayer money went, where the farmer-paid assets went. However, as you say, there really hasn't been anything happen that I'm aware of.
On October 5th, 2016. See this statement in context.