I really don't think it has anything to do with betting. There is something else going on, probably related to the WTF but I still think there is something else to it. The tennis equivalent of a "dirty protest" in prisons. I don't gamble at all, but after the first couple of points it was obvious that Tsonga was deliberately losing. I didn't watch the other matches of the same ilk, but I imagine they were all like this one. Some players like ND and Murray might just be a bit better at disguising it. Actually the only player who has come out of this farce with any degree of integrity is the Fed, who refused to play at all. Mind you he seems to be able to get away with it. Not so easy for the rest.
To be fair, the organisers knew forever ago, which is why they are trying to get Paris moved to February. Don't know if they have much chance, with the US erm, imbalance on 1000 events. And then Toronto, just to rub in the North American stranglehold.