Travel to Antonica (near Wiz Spire / Druid Portal), and click on the large stone at ( -2247, -14, -247 ) Copy/waypoint -2247, -14, -247 to enter the one-time instance A Buried Hideout.
Similar to the last quest, the quest text still prompts you to summon the Spirit of Giidib by activating the Shard of Marr in order to find the location of the instance. You no longer need to do this.
Enter the hideout and kill all the monsters. Then double-click a captured froglok to release him.
For a little fun, although not really needed for solo mobs, there is a rock near the entrance you can throw that will bring the single mobs to the top. The rock respawns quickly to throw again.