You are to blame. You are asking for an extension of new credit (even when you are moving existing credit lines). Checking credit is part of the extension of credit.

BOA would reasonably want to know if you have perhaps applied for other credit since you last applied for credit, be it 1 day or 1 year.

There is nothing you can do at this point. The best effort is by BOA saying it inadverdently pulled your credit a second time (which isn't quite true).

Going forward, it's important to clarify the ground rules before starting any conversation. Banks are quite rightfully trigger happy on this stuff. When bank examiners do routine audits, if this call gets pulled you can bet that an examiner would ask to see the pull associated with the "extension."