Wash/clean 2005 Sienna cargo area (rotten milk)

I recently bought a 2005 Toyota Sienna that was in near pristine condition
until we forgot a half gallon of chocolate milk in the cargo area.  As it went
bad it bloated and started leaking.  The carpet and pad is damp and the
car smells like a dead animal.  How do I clean this area?  Is there a drain
such that I can wash/soak the area and excess will drain out while I dry the
rest with fans? Other ideas?  I'm hoping not to remove all the plastic to
remove the carpet, but if that is necessary, please provide tips to do that
without breaking the clips/pins.