Sure. They know the raw hardware capabilities, they know how to jam it and turn it off. You can't use weapons supplied by a friend of your enemy or your enemy. That's basic commonsense.
The S-400 will use our own datalinks and network. The Russians don't have access to that.
And the thing about "they know how to jam it", nope, they don't have that power simply because we can use custom generated signals which the Russians are not aware of.
So if they can't get access to our C&C or recognise our signals, they can't do anything to our S-400. It's as simple as that.
Now, the US can do that with the F-35 because the Americans will control the F-35's C&C, and the F-35 is not programmable by anyone but the Americans. Take that away and even the Americans can't do jack to the F-35 either.
The only advantage the Russians have is familiarity with the system, which can allow them to take advantage of any inherent weakness. But if they want to defeat the Indian S-400, they will still have to do it the hard way.