Hi. I agree with Culver, except on one point. In Colorado you can legally tape any conversation in which you are a participant or for which you are physically present. Clearly if the tape is of him abusing you, then you are present and the tape is both legal and admissible.
You do need an attorney, if only to help you prepare proper paperwork to respond the CFI report and ask for appointment of another CFI, or to hire your own expert. In Colorado, as in many states, lawyers can now provide "unbundled" legal services, which means that they can write your pleadings for you, give you advice, including how to handle a hearing, but not actually enter the case. This is usually much cheaper than hiring a lawyer to handle the whole matter.
Good luck. jim
NOTICE— This answer is provided solely for informational purposes and is necessarily based upon an incomplete statement of the facts and circumstances of the problem. The response given is based upon the limited facts provided by the person asking the question. To the extent additional or different facts exist, the response would change. The response should be used as a starting point to understand the general legal issues or to frame the issue when seeking specific legal advice. This answer does not establish an attorney-client relationship.
There is good news and bad news... Some CFIs have biases, but most of them are looking exclusively from the child's perspective. If there is some form of allegation that does not involve the child, it doesn't always make it into a report. It sounds like you are pretty deep into your case. If you are doing this without representation from an attorney, or without confidential guidance from an attorney, you are probably not on the right track. Under most circumstances, you can show a recording to a CFI, but it could be illegal to have recorded the conversation under other circumstances. You need confidential advice. Bring the tape to your lawyer.
Sign up to receive a 3-part series of useful information and advice about child custody law.