Yes, it is possible for someone with about a week's experience in a 3d modeling application to get a simple humanoid custom animated model into a video game within 20-30 minutes. People who take up arms and say, "It can't be done" will never be able to do it. If you want to learn how, go to http://trepaning.com and download the Unreal 2004 character model video tutorial. If you want to keep believing it can't be done unless you're a pro, then cover your eyes, ears and mouth, and carry on with your beliefs.
http://trepaning.com