Interesting.
First, the controller was obviously not doing his job properly, in that he neglected to pass you the traffic which was headed your way, or make sure the traffic stays out of the way.
Also, the fact that you couldn't get in touch with the controller is also weird, since it seems he was having a long conversation with a pilot.
Had he been talking in english or french with that traffic, you still wouldn't have been able to get in contact with the controller. And its no guarantee that you would have spotted the traffic either. So dual languages is really a secondary issue here.
Now i understand that had the controller spoken to that plane in english, you might have tried to figure out where he was and what he was doing, but that's a lot of if's and maybe's. Again, no guarantee that "english only" would have spared the TCAS RA.
Seems to me poor ATC procedures is entirely to blame.
Thenoflyzone