maybe not dungeons, per se, but I could certainly see small events akin to guildhests being used. a few examples:

Gridania DoH/DoL Guildhest: "Dam It!"
Description: The Shroud is in danger of flooding parts of Gridania. Your party must collect logs and build a dam to prevent massive damage to the town.
4 Man Group: 1 BTN, 3 DoH (like carpenter, alchemist, leatherworker, blacksmith)

Uldah DoH/DoL Guildhest: "Our mighty mighty brickhouse"
Description: Local denizens' homes are falling apart. Stones must be collected, support beams need to be built, and roofs need to be thatched--we can't just let it all hang out.
4 Man Group: 1 Miner, 3 DoH (like carpenter, armorer, blacksmith, weaver)

Limsa DoH/DoL Guildhest: "We put fishsticks in our mouths"
Description: A large envoy has made a surprise visit to the town. Your team must quickly gather supplies and prepare the hall.
4 Man Group: 1 Fisher, 3 DoH (like culinarian, alchemist, goldsmith, armorer)