I dont wanna be a bearer of bad news but.. no such thing as being anonymous(completely hide your telegram profile including telegram_id) from the bot (neither operating with longPolling nor with webhook).. the bot developers might decide not to use/reveal your identity from others(or might even decide to automate the process so that even they wont take a peek like without even writing the user ids in while writing logs) but telegram will send the identity to the bot handler regardless (no such feature is baked into the current telegram bot API). TL;DR: your "anonymity" is at the mercy of the developer of the bot.