Have your agent call the former listing agent. I strongly suggest you have your own buyers agent because foreclosures and REO's are a lot more intricate and have many more pitfalls than a traditional retail transaction.
During the redemption period you really need the sellers cooperation. The bank cannot do anything to accept your offer without the seller signing off.
Please get representation.
Worst case, your agent can try contacting WAMU so they know you are interested in buying AFTER the redemption period is over.
Talk to a real estate attorney on that one, but I think you're SOL for now. A short sale is negotiated with the seller then presented to the bank. As the property is in the redemtion period following foreclosure, I don't beleive a short sale is an option. I think the bank needs to wait out the 6 month period before getting the courts to declare the home abandoned so they can take posession then sell it.
Technically, if you could contact the prior owner you could pay off their redemption (missed payments plus interest, penalties, etc) and get the house out of foreclosure THEN pursue a short sale, but there are no guarantees and thats a big leap of faith.
So my guess is you probably need to just wait it out or look at other properties