The third Dragonlance module is also a bit of a surprise if you are mainly familiar with the world through the novels. Although set during the events of Dragons of Autumn Twilight, the truth is that many of the events here are not adapted in that novel. In fact you would have to wait 23 years until 2007 for some of the events here to be adapted in novel form in Dragons of the Dwarven Depths. 

In this module you and your party of Dragonlance heroes are shepherding the refugees of Pax Tharkas which you liberated at the end of DL2 to a safe place where they can avoid the incoming dragon armies. You are also looking for weapons which might benefit you in the war and looking for the entrance to the Dwarven kingdom of Thorbardin.

This leads you to Skullcap under which is the entrance to the lost Dwarven kingdom but also the lost tomb of Fistandantilus, legendary wizard of Krynn and a bit of a demilich by now. Another fun Dragonlance adventure, which is heavy on story and light on player freedom, so it might suit you and your player or not, depending on how much do you want your DnD game to be interactive fiction rather than a more loosey goosey affair.