Interesting question - What is "mid-June"? The 10th, 15th, 20th? Why didn't Woodward give the exact date when he revealing everything else but the "former" official's name? It makes a big difference here .....
Presumably he did to Fitzgerald but since he is still attempting to protect the identity of his source, he may have wanted to avoid being too specific to make it too easy for someone to check out travel schedules, meeting logs, etc to find out who Mr X is.