Missing Main Quest Line

ISP:
Cox

Type of Internet Connection:
Cable

Internet Connection Speed:
40mb/s

Date & Time:
6:00pm Arizona Time

Frequency:
Once, but still lingering

World:
Cactuar

Character Name:
Yin Kittenstouch

Retainer Name:
none

NPC Name:
Marques

Monster Name:
None

Class/Level:
BLM 33ish

Party or Solo:
Solo

Race:
Miqo'te F

In-Game Time:
Uhh I didn't take note, it happened yesterday.

Area and Coordinates:
Church of Saint Adama Landama


Steps:
I had just completed the quest "Eyes on Me" When the correlating NPC's for the quest line disappeared. When I looked in my completed log it told me that I should look for an airship in Gridania but I'm without a quest to do so nor am I able to find a quest giver anywhere to continue the main quest.

According to this page the requirements for your next main scenario quest has been changed - it now requires a sidequest called 'Plagued by Indecision' to be completed before 'He Who Waited Behind' becomes available. Apparently it's from the same npc however so all I can imagine is you may already have this sidequest unlocked and incomplete (which would explain why the npc disappeared) - to verify check your Journal and see if you have this quest still listed as 'current' under 'Thanalan sidequests'. This page explains what you need to do.

Sadly I do not have that quest either. As you stated it would be given to me by the same NPC I'm missing.