Debbie Gibson played at the Bourbon Room last night and Joey made a surprise appearance! They talked a bit about working with Sean Thomas and how they decided to record a song together for her Christmas album. Then they performed the song "Heartbreak Holiday" for the first time ever together! They sang it twice because they were taping it (they didn't specify why). Here is a video shared by @artzgal78! Joey comes on stage around minute 33.
Here are a few other clips from other angles:
Debbie posted this video of them getting ready backstage!