Sorry if my answer is late
You can very well handle all your page traffic through just one bot backend
- Create an fb app and select product as messenger
- Add webook config pointing to your bot
- Select all the pages you want to associate one by one
And keep the page access token handy.
- Go and search page id in your fb page and keep it handy
- Either in constant or dB maintain page access token against the page I’d
- When you get a callback on webhook you get a page entry and Id== page id
- Based on page I’d have your business logic
- Call send api using page access token which you have stored againtst the page id
Hope this helps