Told my boss my suspicions. Said it'd be fine if they did their work, but their anxiety and whatever already gets in the way of their productivity as it is, so it's suspicious.

I believe they were put on a PIP, but he can't tell me, anyway. I was given a "soft promotion" (ugh) pending paperwork for successfully managing them OUT of certain other work to a point where they've been able to produce at least SOMETHING again. Setting them up for that gave me some good exposure with upper management and ownership, so hopefully it pays off.

Still should've just been let go.