Pass values from a database to dialogflow to avoid asking a required question, if the value is in the db using Python's dialogflow_v2

Question

I set up dialogflow with the following parameters and actions

As you see i have 3 required parameters. Eventually these parameters are going to be saved in the database. So what i want is a way to pass these parameters to dialogflow (if i have them in the database) and somehow "toggle" the required option.

There are 3 options:

1. Its a user who uses the chat bot for the first time so i want all of the required parameters to be asked to him
2. Existing user who did not consent on his data to be gathered (i want to save that hi didn't consent and make dialogflow not to ask him about that again) (parameter:consented)
3. Existing user who consented, so no required parameters should be ask and only match user's text to an intent

So if i have the parameter "year" for example in the database i don't want dialogflow to ask "what year are you in ? " Just skip it and go to the next question.

I've encountered fulfillment for slot-filling, but there are 2 problems with it, first of all i am not entirely sure whether this is what is meant for, and also the documenation I didn't find the documentation to be very helpful.

The code that i have up to now is :

I am using dialogflow_v2 of python on telegram

def detect_intent(session_id, text):
    """Returns the result of detect intent with the query text as input
    Using the same `session_id` between requests allows continuation
    of the conversation, if context handled in dialogflow
    Also, gives a dictionary of parameters needed to fulfill the intent"""

    session_client = dialogflow.SessionsClient()
    session = session_client.session_path(PROJECT_ID, session_id)

    text_input = dialogflow.types.TextInput(
        text=text, language_code=LANGUAGE_CODE
    )

    query_input = dialogflow.types.QueryInput(text=text_input)
    response = session_client.detect_intent(session=session, query_input=query_input)
    dict_response = MessageToDict(response)

    return dict_response

and basically I keep calling it untill all required parameters are filled in

    if response.get('queryResult').get('allRequiredParamsPresent', False):

Anyone that knows how to do this or can suggest me on where to look ? whether is through dialogflow_v2 or fullfilment for slot-filling.

Thanks in advance!