Then what your going to have to do is demand an audit of the escrow account from Bank of America. They have the duty, obligation, and liability to give you an accounting of the escrow account.
Mortgage escrow accounts are covered under the the RESPA and HUD regulations.
Since 1976 the RESPA statute has allowed lenders to maintain a cushion equal to one-sixth of the total amount of items paid out of the account, or approximately two months of escrow payments. If state law or mortgage documents allow for a lesser amount, the lesser amount prevails.
What you should do is formally demand a mortgage escrow statement from Bank of America for the last two years. You should send the demand by certified mail, return receipt requested to the address where you pay your mortgage. You should state on the letter you account number, the old account number, and anything else you have about the loan.
If they don't send you the information, then I would contact an attorney and file suit in the matter - they must send you the information once requested.
Once I received the information, I would send the information off to a forensic mortgage escrow analysis company and have them review the matter. It very well could be that you have been way overcharged, they have potentially made payments late, or are just incorrect in their calculations.