Agreed. But if forced to testify in court you would commit perjury if you said you didn't sign it.

If it came out that you intentionally mislead the other person by signing [a false name] [to get out of the obligation], good luck, you're still on the hook and now have opened yourself up to potential criminal and civil fraud charges.

Don't think you can skirt not taking the stand. More than likely this will be in a civil trial and not taking the stand will be viewed by the court and jury that you are hiding something...