The Realm Of Light - Glitch Help Again

Hey guys, back at it again with more quest glitches. I was doing The Realm of Light quest, when it suddenly broke for me. I just got bit by the dog, and need to speak to the npc Regulux, but I can't. Why? Because he didn't spawn in the room, and you can't leave the room unless you talk to him. And it's not like he just didn't spawn in at all, I can see his nametag through the floor. I'll try to leave the room to find him, but then I get the text "Wait a minute! You're probably confused. Allow me to explain what's going on here." and then I get teleported back where I started. How do I fix this? /class did nothing, and I can't click on him to trigger the dialogue through the floor.

 

Try switching worlds an if that doesn’t work, try restarting minecraft

 

/kill and do everything again.