Unfortunately it is true. Even the part where Stan sings Oliver North got off scot free. I had to double check that, because I thought for sure Oliver North was convicted for his role in Iran Contra, but on 9/16/1991 all charges against Oliver North were dropped.

This is a pretty solid summary of the Iran-Contra affair sing by a cartoon character. It actually does a pretty great job of covering all the major events in under two minutes

One thing left out of the song was that the original weapons trade to Iran was for US hostages being held by Iranian backed militants in Lebanon. For many Americans this was the worst aspect of the scandal - the Reagan administration negotiating with terrorists just a few years after the Iranian embassy hostage crisis.