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You wrote about subscriber notifications, and to get subscriber notifications via the API, Webhooks or PubSub requires a user token from the broadcaster. Yes a chatbot can read them from Chat anonomously or logged in as a User account, but that is unclear where you are getting the notifications from.
Yes, either use the token that you are using for the bot to login to chat with, or use a server to server token aka App access token aka “client credentials”