I Can't Talk to Chuck

Throwaway account for obvious reasons. I am the cofounder of a start-up that is just starting to gain quite a bit of momentum–all the hard work is finally starting to pay off. Our business involves sending payments via check to people, and we use Schwab to handle that side of the business. This morning, I opened the bank account as usual to check the balance, only to get with this message: 'This account is now closed. If you feel this account was closed in error, please contact customer service at 800-435-4000.' We have tens of thousands of dollars of checks outstanding (this is usual), and an account closure would mean that anyone trying to cash a check would get a message saying the check had bounced along with a 'check bounced fee'. To minimize the damage, I immediately got on the phone and started talking with someone (person #1); she put me on hold for half an hour, and I finally got to talk to (person #2). Person #2 was nice, but told me she couldn't do anything to help me, except forward me to the Client Advocacy Department. That's where things went sour. The man (person #3) I talked to in the Client Advocacy Department was extremely rude. Finally, I asked him a question, to which he replied, "Well, your account is closed!" and straight-up laughed at me. I said "Is there someone I could speak with will try to help me instead of laughing at me?" He said "No, there isn't." At that point, I decided to visit my local Schwab–it's right up the street. I got the same story–we can't reopen your account or tell you why it was closed or help you in any way. The best we can do is give you a lump-sum check for the value. Finally, person #3's manager called me–supposedly the highest-level person in Schwab you can talk to. He was extremely rude–even just remaining silent for long periods of time when I was done talking. Anyway, the rudeness/bad customer service is okay, because that's the first time I've experienced it. What's not okay is that this move on the part of Schwab to unilaterally shut down the account without reason (no one will tell me) is ultimately going to destroy our start-up (and any traction it has along with it) as well as make it hard for thousands of people to get money that is theirs. So, HNers, what can I do? I'm extremely frustrated, and I feel like I'm out of options.