Int + Crafting or Int + Occult, target 3 successes to witness the fleeting change in the earrings and realize they are made of
Hermium. Either your dots in prime or in matter can be used as equip modifier for these rolls.
Int + Occult - 3 to recognize the patterned Spider as a legacy
yantra.
You can decide to accept the gift or you can refuse it, it's up to you. You can investigate the umbrella with a wit + investigation or wit + craft roll, if you do, I suggest you do it once inside, free of environmental penalties.
Neither of you has supernal vision or a sight spell with enough potency to defy their transform aura or defeat their incognito presence, which according to the Mage Errata don't trigger unseen senses. Since you didn't have a mental shield up, unless something memorable occurs, you'll probably forget the encounter, as those two register for all intent an purposes as Sleepers. Yet, you have enough details/clues to proceed with this plot line if you wish to continue interacting with those NPCs. Woman has high fame, but I'm sure there are enough fate/space/forces/prime/matter dots in the group to be able to trace them back regardless of any sympathetic penalty.
Campanella has caught the imperceptible sign of a mage spell even if just for a fraction of a second. So you have some margin.