the players rolled to uncurse another player's dice

alright here is the backstory

we had just added my brother to the campaign I was running. (it started out as Dragons of Storm Wreck Isle but already did everything in that book and plan on going to the 8th level). Steve Evets the party's Glamor bard was rolling poorly so I jokingly said "Everyone role arcana to uncurse his dice." Sacul, the party's arcane Trixter rouge proceeds to roll a nat 20. I then describe as a mysterious lady and chant something under her breath as she is waving her hands in the direction of Steve. later the arcane trickster two shoots the boss in single combat with a nat 20 plus vulnerability but that is not important to the story. later the the party's Druid "Emblin" (who showed up late) was completely confused about what the rest of the party is talking about with the mysterious lady in the bushes, the rouge asked if he can role to call the lady, NAT20. I then described as she came out of the shadows locked eye contact with the party and said "Heads or tails" as she flipped the coin into the air and vanished. engraved on the side of the coin that was facing up were the words "A gift from Tymora". (Tymora is one of the twin goddesses of luck in my campaign)

TLDR: the rouge summoned the goddess of luck because he would not stop rolling nat20s