Assistant to the Assistant Guest Relations Manager

Edit: As this is the top comment, for visibility purposes I'll try to keep it updated every day until we finish this achievement, because Wowhead is so slow to add stuff.
Just FYI, new quests become available every day at 4PM Central European Time.

Edit2: I've maxed out post length. The whole reason why I made these comments was because there was no information on how to do these quests before Wowhead was updated. Now there are guides, so there's no reason for me to keep older information in these comments. I'll just keep it updated with the latest content that's not on Wowhead yet and provide links to guides for older content.

Here we go:

All the local stories for Assistant to the Assistant Guest Relations Manager

"The Case of Misfortune"

Deck Dismay

Day 5 guide

"The Case of a Good Book"

Restoring A Grand Tale

Day 6 guide

"The Loud and Smelly Case"

The Case of the Fur-Getting Wikket

Day 9 guide

"The Case of an Old Soul"

Nola's Last Wish

Day 10 guide

"The Case of Great Aspirations"

From Ashes to Wisdom

Day 11 guide

"The Case of a Feathered Friend"

A Bird's Tail

Day 14 guide

"The Case of Missing Mementos"

Lost and... Found?

Day 15 guide

"The Case of of Pet Games"

Battle Pet Bingo

Day 15 guide

"The Case of Staged Disaster"

The Show Must Go On

Day 16 guide

Credit: WoW Secret Finding & Collections Discord server, channel #guest-relations-secrets

Per Blizzard this event will not start until October 28th Article Link

"Often a thankless job, guest relations has a new volunteer, Alyx, stepping into the role with the lofty hopes of doing a better job than their predecessor. As visitors pour into the celebration, Alyx is under pressure and could use a little help making it an event to remember. Thankfully, they have found a secret-sleuthing tuskarr family who have become the perfect helpers in getting players up to speed with the tools of the secrets trade.

Assist Alyx each week with resolving new guest mysteries by using your new secret-finding skills, and be on the lookout for stolen celebration goods. Follow the rumors and solve the mystery— if you can. We’re counting on you, secret finders.

Players can begin working on the initial secrets beginning on October 28 with additional secrets opening up on November 4."

What is my perfect crime?

I log into World of Warcraft at midnight. Do I farm gold? No, I go for a rare mount. It's priceless. As I'm about to loot it, a player catches me. She tells me to stop. It's her guild’s raid. She's the Guildmaster. I say no. We quest together all night. In the morning, the GMs come but i escape dressed as an NPC. I tell her to meet me in Stormwind, but I hearth to Winterspring. I don't trust her. Besides, I like the cold. Thirty expansions later, I get a message. I have a son, and he's the raid leader of Liquid. This is where the story gets interesting.. I tell her to meet me in Dalaran by the fountain. She's been waiting for me all these years. She's never joined another guild. I don't care. I don't log in. I go to Ironforge. That’s where I stashed the rare mount.