So she got BS from BS

To be fair, my guess about the source of those claims is also totally unsubstantiated and quite possibly bullshit 😉

Does she hold any investment in BlueSky?

Imo, it’s way more likely she got her information about BS from the website/a press release/a contact at BS and like you said, didn’t bother to get a contrasting opinion from anyone associated with Mastodon (probably because it’s a lot harder to get ahold of someone from a distributed project like Mastodon).