Ah, the wedding. WHOLE LOT of Wamps all tgoether, politically needed...
...if Mab is peeved at the WC for something....
red wedding?
This will be the first big Whamp shindig (AFAIK) since the debacle at the Raith Deeps... where Skavis and Malvora got most of their top ranks wiped out; they're fringe players now, I think. The Raiths
own the White Court now, until another House gets some of their mid-tier powers older & more puissant (and simply fill out their numbers a bit! They don't have enough members to implement credible schemes & threats) IIRC, whamp's can't breed very fast (and terror/despair are hardly the reproduction-enhancing emotions for feeding that lust is!).
I don't think Mab has any grudge against the Raiths; if she did, she likely wouldn't be ordering her Knight to marry a princess of Raith... and that's doing them an honor.
It's very possible that she suspects (or even knows with surety) Nemfected Justine has put some further Outsider-mischief in place among the Raiths, and
that is her objective (or rather,
one of her objectives).