Greetings,
I can build the dialogflow bot for you. I will just need to listen to your use case, and then I will be able to build it.
I already have a dialogflow chatbot connected to facebook. If interested , I can send you the link so you interact with it first, to have a feeling of it. You can then decide whether to award me the project or not.
Contact me via chat so we get started. If you need to test my bot first, then request for the link in chat.
Looking forward to hearing from you.