[Eukie]

I'd probably say that this is a combination of two or three kinds of Psy-Ops (SE62) (Undermining trust, giving information, and a whispering campaign) with viral "marketing". I'd also say that since it targets specific people in a limited group, rather than a specific demographic in a large group, a regular Approachability roll (SE25) is more appropriate than market research.

The core of the social attack is a Quick Contest of Psychology (Applied) + Going Viral vs. Alex' Will. Psychology (Applied) + Going Viral is complemented by Politics or Savoir-Faire (High Society), and penalized by the reverse of the modifiers Harriet has on Loyalty Rolls towards Alex.

I'm not entirely sure what success and critical success would mean; probably giving Harriet some penalty to Loyalty Rolls against the target population, and/or giving the target population some bonus to their own social rolls to convince others that Harriet is temporarily unfit to do her job. On a critical success maybe even inflicting the target population with a Delusion.

Really though, if you want this to work you'd probably want to work multiple angles; Giving (false) Information that Harriet is tired, starting a whisper campaign in the populace that Harriet is tired so it filters up to the politicians, making individual politicians believe Harriet is tired, and finally pushing for the vote of no confidence.

The last part is best done by finding someone who'd benefit greatly from Harriet losing that vote, and giving them an opportunity to do so.