No, the 1954 Godzilla movie was one of Godzilla's earliest works, but it was not the earliest. The name Godzilla first appeared in a Japanese manga of the same name in 1942. Before that, there were other forms of Godzilla's image, such as appearing in news reports, posters, and advertisements.
I'm not sure specifically as there could be many different 'Madison game stories'. It might be about a character named Madison in a game. Maybe it's an adventure story where Madison has to overcome various challenges in a virtual world.
Yes, the Ashley Madison affair is a true story. It involved a significant data breach and exposed the personal information of many users of the website.