My guess is that this is going to be like the early days of the Roadster. Tesla wanted to focus and not build things they didn't "have" to. But customers wanted more charging flexibility, so the third-party RFMC was born. Eventually Tesla came out with the UMC, and it was better. (Well, generally. The one I got didn't work, and left me in a tough spot in the middle of nowhere--Shingletown, CA. To be fair, I only bought it because my RFMC had failed too. There is nothing like having two charging solutions that don't work!).
I have heard of at least one independent company looking at building a CHAdeMO adapter for the Model S...not that I'm sure that can be done without Tesla's cooperation.