Any chance Fatima has heard of this Adivon Adrissant? (Lepidstadt U. isn't a magical school, but maybe he's well-known enough there …). She does not have Know (local), so maybe just an Int. check? Also rolling Know (arcana) and Spellcraft to see if she recognizes the apparently non-standard phantom steed.

(1d20+4)[17] Int.
(1d20+8)[14] Know (arc)
(1d20+8)[12] Spellcraft