Decompile an ancient game (.exe)

Since I am a student on a limited budget and I have absolutely no overview of how difficult of a project I am handing out, I will leave the price open for people to suggest, that is the only fair thing to do, so drop a price you believe is appropriate. Here is the project: There was an online game published in 2004, and in 2015, when the company that made the game was facing some issues and was contemplating shutting down, they made the game available as an .exe for people to download. I have downloaded the game, but it won't work, not for me or anyone else. There are some people in the community that believe they can re-make the game if they can see the source code, but the issue is, none of us know how to decompile the game. PEiD says that it was written in Visual C++ 2008, but I don't know how that is possible as the game was published in 2004, and while it was online, it depended on the Shockwave Player to function. Thank you, looking forward to feedback.