There are a few things that might support the theory I've made up top.

Evidence 1

The Puppet

You know the lyrics in BIG SHOT? The freedom motif one? Yeah, so lyrics contain something along the lines of 'He pulls the strings and makes them ring'. There is a lot of speculation as to what this means, but I'm looking at the bigger picture. Who controls the worlds and decides their fate? Toby Fox himself, he even said the ending came to him in a fever dream. His fever dream.

Evidence 2

The Q&A

This is a bit of a sceptic one with not many facts to back it up, but here is a piece of the Deltarune Q&A

Hmmm... So before I hear and stuff like "THAT'S JUST SPECULATION!" in the comments, I want to remind you that that's true for this piece of evidence. It may at most loosely tie in with my theory.

So as I was saying, highlighted in blue it says "There's something more important than reaching the end." This could refer to a lot of things. But maybe it means you have to find someone... Maybe finding the one who was behind everything is more important then freedom or reaching 'the end.'

Evidence 3

The... Toby Car Scene?

Okay, here me out.

This is a quick one. So finding an secret room is cool right? Maybe something good lies at the end, like items, Dark Dollars or Lore... I think Toby is here purely to hide what's at the end of that road. Maybe something you as the Player or Kris themselves, aren't supposed to learn.

In Conclusion

Congrats! You read my crazy wack theory! (Or skipped to the end.)

I'm sure there is tons of things wrong with this and I'd love to hear them. Either way, I'd think it would be cool if Toby was the one behind it!