The follow-up.
So after all was said and done, I got a call last Thursday from the people at Octagon. Turns out that I did do a good job and that I had impressed them. I was told that I would have gotten the job had it not been for the fact that the Managing Director decided to extend the contract of the co-op student they have currently on staff so that that person would just continue part-time into the summer. So they saved a few bucks. And after all that stress...
Good to know that my French isn't all *that* bad.