Assuming I'm not contradicting canon material, this could be the reason as to how Riku found out the King was in Twilight Town in Days. Anyhoo, let's get back on track.
Current Location: Dark City, The World That Never Was
Word Count: 182 words
Days VIII - Status Report
"So after you saw Mickey, the portal brought you back here?" questioned Riku to Pluto. Human to dog communication was easy as can be, though the same can't be said for other way around. Riku had minor trouble trying to discern which barks meant "Yes." and which meant "No."
Fortunately, it seemed Pluto's most recent bark was a yes.
"Interesting. You've been a lot of help, Pluto. Since I fear the inevitable will happen to me once all this is over, I'm going to have to have a talk with the King. You said he was in Twilight Town. Right?" Pluto nodded. It may have just been a few seconds, but the dog knew what he saw.
"Got it. I'll be back soon, think you can hold down the fort here until then?" Riku created a Corridor of Darkness before them. Pluto sighed, sad that he wasn't able to join him. But relunctantly nodded.
"One thing though. By the end of the day. I probably won't be me anymore." with that. He disappeared into the portal, leaving Pluto alone in the city.