Mystery of the Vanishing Lo Pan

Gunner's Mate
Apr 01, 2013
I fought Lo Pan yesterday, and I'm concerned about the following.

After getting Lo's health down, he will command his minions to finish us off. Then Old Scratch says that when his minions are defeated, he will return even more powerful. So I defeated the minions (Easily), and Lo Pan didn't come back. Then only his chest appeared during the end of the fight, and I only got gold.

Is there anyway how you can fix this bug?