The Blood River Fortress on the first layer of Hell is where news travels the fastest.
That's mainly because there are a lot of people and it's bustling, with a high density of devils, so rumors spread like wildfire. Plus, any devil that can come and go from the Blood River Fortress tends to be of significant status, and they each have a bunch of greater and lesser demons surrounding them.
With the encouragement of the Grand Duke of Hell, the ridiculous bet made by Amberser quickly spread.
However, the versions varied.
Everyone knew that legendary character had gone mad, actually trying to end the Blood Battle.
It quickly became a joke, "The Deceiver has gone mad" became a greeting phrase amongst the devils.
Have you heard? The Deceiver who could even scam the Grand Duke of Hell has lost his mind. It's said he couldn't handle Zariel's squeezing, mortals are just mortals after all.