It may never be used, but it's not rumors and hearsay if it comes from the actual person. This isn't outside people speculating, this is proof that at least some internal people are considering resignation.
They resigned is incorrect. Hearsay is when one person is reporting what another person has said, which isn't the case here: it's coming from the source. Rumor also does not seem a good word to fit this situation when it's coming from the source.
