To the OP, per Pilots Bill of Rights, you are entitled to receive a copy of the communications data file and transcript. If you read back the instruction incorrectly, and ATC did not catch it and correct it, then this could be re-characterized as an OE (operational error) on ATC instead of a pilot deviation.

Also, if the Brasher Warning was not issued to you over the VHF, then that is another technicality in your favor.

File the NASA report, and wait. If you are an AOPA member, sign up for their Legal Services Plan.