discredit the truth and truth seekers.
But he didn't say, "I don't have a Twitter account."
But how does a "fake account" get 11,000 followers in nine months? Why would he tolerate it? What "Giuliani" says in his Statement is true. It's possible he was spurred by his rejection for Sec. of State.
It's also possible that this is a "fake news" psy op. i.e. A phoney RG reveals the truth and then the real RG denies he said it. Thus the real truth is discredited.
My view is that the truth is never a hoax. I am concerned however that this Statement wasn't on his official Twitter account, the one with 70K followers.
As Glen says (Comments), this does seem "too good to be true." But I'd rather be thought gullible than risk discounting a genuine whistle blower. I believe man's higher nature does shine through and will triumph.