If you use just 1 OAuth token and it says you’re missing a User OAuth token, it’s because that token isn’t a User Token.
Use the Validate Tokens endpoint https://dev.twitch.tv/docs/authentication/validate-tokens with the token. If it doesn’t include a login, user_id, and the channel:read:redemptions, it means you’re using the wrong type of token. Also, that user_id associated with that token MUST match the broadcaster_id of the channel point redemptions you’re attempting to get.