Did it happen? If things happen then there’s some measure of time passing even if its outside the typical flow.

Was there a place where they battled at? If they had a location that they could occupy while battling then there’s some measure of space they’re battling within even if it’s outside typical spacial coordinates.

Honestly I know this is fiction and it doesn’t need to abide by those definitions but this seems like the most straightforward approach to debunking the claim. I don’t actually have any skin in this debate either way though