Route web widget directly to a specific answer/flow using zE('messenger:set', 'conversationFields'... and branch on condition?

Use case:

I have a spot in my app where someone can click a button to fill out a form. I'm currently doing this via Google's dialogflow CX, and trying to move things into Messenger… the business work flow is that the form needs to be a ticket anyway, and we want to get onto those form submissions as quickly as possible. 

In the Core API docs, it suggests the exact use case - to set a conversation field while also using the API to open the chat:

Also, if you want to make sure that your conversation fields were set properly before opening the messaging Web Widget, then you would call..

My question then is, how do I use this conversation field in the Flow builder? It seems that the only way that the branch by condition can use a conversation field is to first have a step before it in the flow builder that asks for that field to be filled. Now the field is selectable from the UI of the branch by condition.

But I don't want the user to be asked for this field first, it should be completely hidden from the user?

In actuality, the whole idea of using a conversation field to route to an answer is a hack… the product ask here is to add to the API the ability to force messenger to open to, or if already open, to jump over to some specified Answer such that regardless of what answer flow the user left off in, upon that API .js call, it would force Messenger to start at the top of the specified flow.

In my use case - it would be to go to the “apply now” Answer flow, which would have the request information step, so the user could fill out the application, or ask questions about it. Because they would be in the “Apply Now” flow, I can more easily route those questions to the team that works that part of the business.

Note this is not the only use case… there are other cases where there is no form to surface, but if someone clicks on a button that says “get more info about XYZ” - I would like to be able to pop open the chat, once again to the top of “XYZ Answer Flow" which could simply have the bot now say - here is the additional information about XYZ… did that answer your question or do you want to talk to someone? 

Essentially this saves the user from having to type in their question if I can give them a button to click on.