Is it a one time event? If you missed it, is there another way to get the armour.

Also, that you can get layered Oolong with 5 VIP tickets and different colored pendants with 2 or 3 VIP tickets.
Tip: Use 5 pieces of Oolong armor a+ and join low/high rank SOS in which the leader is MR 0. (Got 5 tickets straight doing that with HR SOS quests)

Clarify that there are 2 Joyful Tickets:
●Joyful Tickets, you get when login and doing limited bounties.
●VIP Joyful Tickets, you get them by completing MR quests, or by Low Level Hunter Helper rewards randomly. Oolong armor a+ helps to get them easier.

I think you have "A Chilling Entrance" Wrong (on the Xbox anyway). That event has you slaying a Black Veil Val Hazak & Velkhana.

The Quest that has you slaying a Velkhana & Namielle is called "The Winter Blues" and that one gives Bonus HR/MR.