It's never mentioned that the value of time and distant doesn't exist in the hiddin world, just that "it doesn't matter"
NT Vol 10
“Oh, Niang-Niang. Where have you been?”
“The concepts of distance and time don’t matter here, remember? And I can’t leave regardless. Even if I did, I’d just end up gathering unwanted attention on a global scale like Othinus. I was a hair’s breadth and an infinite distance away.”
“Does the same go for the others?”
“Old man, did you start forgetting things once you became a mummy? The zombie girl, the chimera, and everyone are here. It’s just in destiny’s hands whether we run across each other in this place where the tiniest gap extends to an infinite distance☆”
This is the description of Immeasurable: Movement beyond linear time. This is why the speed cannot be measured. Given that S = D/T, if T is undefined the speed formula cannot be applied.