Colorado is a "one-party" state, meaning that to be admissable as evidence in a court, only one party to a conversation needs to know of the recording - and that can be the person doing the recording so I think the answer is yes. In my state, the answer is no because a minority of states like Illinois require "two-party" (meaning all parties to the recording) consent.
See my Legal Guide Recording Conversations in Illinois
You need a lawyer because I do not practice in CO (I am in Chicago, IL). Check with a lawyer in your locale to discuss more of the details. As I said, I think Colorado is a "one-party" state, meaning that to be admissable as evidence in a court, only one party to a conversation needs to know of the recording - and that can be the person doing the recording. Again, check with a lawyer in your locale.
Good luck to you.
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