Absolutely not true...doesn't withstand the 5th amendment and IMO, the regulation shouldn't exist. Nobody is required to self incriminate under the law.
The Fifth Amendment protects individuals from being forced to incriminate themselves. Incriminating oneself is defined as exposing oneself (or another person) to "an accusation or charge of crime," or as involving oneself (or another person) "in a criminal prosecution or the danger thereof."[36] The privilege against compelled self-incrimination is defined as "the constitutional right of a person to refuse to answer questions or otherwise give testimony against himself".
I returned to a kill sight this year, after a request from a Warden (first time in 39 years of hunting) because it was easier for me to do so than to be a butt about it, but it will be the last time I ever do so.
Oh boy - very good point, never even gave that a thought. That'll open a can of worms.