Under California rules of evidence, the best evidence rule (BER) provides that, where a writing, photograph, or recording is offered in evidence, a copy or other secondary evidence of its content will not be received in place of the original document unless an adequate explanation is offered for the absence of the original. Here, we are not dealing with player b's writing, photograph, or recording, but his oral statement to Mr. Skyscraper. Therefore, the BER does not apply, and the best way to get b's statement admitted into evidence is probably through the "spontaneous statement" exception to hearsay.
See? Direct testimony coming, albeit from a partial participant.
Kevin