Sigfried Not Spawning, What Should I Do?

When I was finishing the hero of gavel trying to get out of the cave with the geyser, I activated the geyser, and Sigfried said something, but the NPC didn't spawn, so I couldn't give him the boots. I tried using /kill, but that didn't work either.

 

What does your quest book say? What happens if you re-enter the cave?

 

My quest book says "find a way to follow the light and escape the cave", and when I re-enter, Sigfried doesn't spawn in.

 

To escape the skylight at the end of the cave?
Can you describe exactly what you did prior to this happening?

 

Sigfried and I are walking into a cave with the second village, and there is a geyser underneath a hole in the ground we have to use to escape.

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Edit: for some reason, he appeared, and I could finish the quest, although it meant I had to sacrifice him