A couple of things:
a) They won by more than 30 points when Tony Parker was not at 100%. (6 pts 8 assists in 27 minutes)
b) Parker's had issues with his legs earlier this post-season and then come back and been more than fine a couple days later. I'm pretty confident he'll be playing in Game 4, though he may not be 100%.
Unless they say for sure he's going to be out, I tend to assume with this sort of thing that the player will be out there.
Even if Parker is not 100% for the rest of the series, I don't think that's necessarily insurmountable, so long as Kawhi Leonard continues to stymie James, Wade and Bosh continue to be up and down at best, and Danny Green / Gary Neal / Matt Bonner etc are hitting threes.
They'll need Manu to step up and play more minutes as a ball-handler and distributor, though.