Let me say, before the walkthrough, that this is my favorite quest and I strongly encourage you to actually read all of the text and enjoy the storyline of this quest. With that said, here's a walkthrough from my in game notes.

Speak with Darshana Machlis in New Trismus at 45880, 14776 (by the landing pad)
Speak with Oriskaly Machlis (brother) in Mahagra at 23748,30545 (up ramp, on balconey, up second ramp)
Port from Mahagra to Bristugo
Speak with Elioncha Shum at 22138, 22646
Port to Genevia from Bristugo
Go South East
Speak with Besoya Shum at 15693, 14437
She asks you to speak with a few people to help arrange the wedding. Speak with the following people in order.
Basiliak Krebs, diagonal across room
Lamorak Dree - 15706, 14290
Souchak Dree- South of Istaria's Loom -16147,13760
Eliahu Krik - same building - 16163, 13765
Joosh Jain - 15601, 14216 **NOTE** If you get rooted, then get a quest called "PSB: Uncle's Conversation, or if you get "Save the Wedding" but don't get an update to Besoya's quest, delete "PSB: Uncle's Conversation" or "Save the Wedding" and talk with Saliash Jain (a different uncle in the same room)
Return and speak to Besoya
Return and speak to Elioncha
Port to Copperton from Bristugo
Speak to Mabrouk Mar (the ex boyfriend/cousin) at 14765, 15796 (NW of the landing area)
Return and speak to Elioncha
Return and speak to Oriskaly
Return to Pajalsti and enter the portal in the Uncle's house.
You will be immediately rooted in place
Talk to Williwaw Carnalis (the only npc in sight) and follow his prompts
Run up the hill and talk to Joosh Jain, follow the prompts (they do not pop up in a normal quest window)
You should receive the orb of truth
Talk to Oriskaly, who will answer the orb of truth questions
Talk to Gaalsif Tudred to get the wedding Ring

Now you must decide whether to save the wedding, or break the vial on Oriskaly.

*note* if you choose to save the wedding, you will get booted from the wedding before you get the quest update for giving Oriskaly the ring. You have to go back into the wedding grounds via the portal, and talk to Oriskaly again to get the update. Then use the portal in the wedding grounds to port back out to Genevia and talk to the uncles.