What happens if both teams try to take a timeout?

What happens if 2 teams try to take a timeout at the same time?

Obviously very unlikely to happen, but if 2 teams tired to take a timeout at the same time, what would happen? Whose timeout would be used, and whose graphic would appear on the screen?
What if the coaches hit the button / submitted the timeout at the literal same exact time? Do you take away an available timeout for both teams? Just for the team that's ahead? Just for the team that's behind? Do we know what's in the rulebook? Any VCT casters / analysts known the answer? Do Riot Officials know the answer? Does it even matter?

Touch grass

2 timeouts one after another. 2 minutes to talk