Antimony starts her research checking the history of local arcane lore any details about local dragon life....and she finds over three hundred years notes about a cave in a cavern where by numerous reports lived a very old deep dragon. After that incident no one went check on it as it was during priestess wars and most forgot the whole case as no one owned nor had any interest on dragon's cavern. Most likely dragon's hoard is still there as report tells the cave entrance had collapsed tightly.....also it would mean the dragon had died in collapse and so it would have perhaps servicecable skeleton for animation. As dragon bones are notoriously tough and resist time of decay longest of all creatures bones. Also in underdark bodies decay slow anyway but it's decent to check out the old collapsed cavern and see what they can work it.