IANAL...but at scale, this might make some libel lawyers rather rich.
I think the emphasis should probably be on the might. If Employ AI (in my head cannon a wholly owned subsidiary of Google, Facebook, or Palantir), decides to use their free legal billable hours (because the lawyers are on staff anyway), unless you get to the level of class action you don't have a prayer of coming out on top.
Not in the US, no. It might have interesting interactions with GDPR and the "right to correct information", though.
This is why you just don't tell people about the libel.
Companies already, today, never give you even an inkling of the reason why they didn't hire you.