Basically, not possible.
Since you are missing “unannounced resub notifications” for when a sub resubs but doesn’t announced in chat.
You can collect a bunch of data, like subs/resubs/hypechat/bits from chat no oAuth needed, but it’s missing the “resubs that don’t get sent to chat”
So broadly, if you want an accurate revenue count, there isn’t any methods for that, with or without an oAuth token.