what? i can understand that a bank asks some questions if you handle big sums of money or have unusually big transactions that you usually do not have, but this sounds bad. do you have to answer them? i would consider to look for another bank.
Yes. If you do not answer and show proof to everything they are asking for, they will put your money on hold for as long as their investigation is running. Funny thing is that I just came from a different bank. I signed up at the bank I am talking about because my previous bank told me to immediately stop using that bank account in combination with Bitcoin. But in general there is not much difference between banks as they are subject to the same laws.
maybe i misunderstood you the first time, but it sounded like you have to give them all the information before you open the account. at this point i would look for another bank, unless they are all the same. if you already have an account and receive/make a payment and they decide to undertake an investigation, then i guess there is not much you can do. but this is one big reason i love bitcoin and hate banks.