Whistleblowers are already protected under current law. Yes, I think that protection is often a big joke, but technically they cannot face retribution.
Potentially losing clearance might be a separate issue, but loss of clearance is a chain of command sort of thing, and if the President wants you to retain your clearance, then that is what happens.
I don’t see why the “disclosure” needs to be delayed.
There's nothing to disclose.
There’s a big difference between whistleblowers and just plain liars.
The fear is of illegal and potentially lethal retribution in practice no matter what the law says. From the UFO crash at Roswell onward, witnesses and their families were often threatened with death if they talked.