Bingo! There is no single person. The deep state may have used her as a cut-out to get the NYTs to bite, but this goes deeper than one person.
This was done to set up an internal war between Trump & his government. Spread panic & paranoia. Cause discord between his staff members. This is a deep state operation.
Whoever wrote the anonymous letter seems to have copied the wording of US Ambassador to Russia Jon Huntsman or actually is Jon Huntsman. But the NYT also could have just used Huntsman’s words to divert attention from themselves, which I think is a plausible answer.