Oh I know. If I gave the impression they go back in time, I’m sorry. They didn’t and didn’t even attempt it.
It’s just a cartoon, after all. :-)
SPOILER ALERT!
But yes they did. That maze thingy at the end allowed him to go back and send the clues to his daughter.
Going back in time, say, on earth, would require that every moment of time is existing in some other dimension. To a non physicist like myself, that would seem to require an infinite number of dimensions