About the vision and its fulfilment, how do you know that you are having the right "vision"?

Are you referring to yourself or are you speaking generally? If it is yourself, I can tell you easily. I know that in your meditation there are times when you go very deep, and your inner voice tells you, on the spur of the moment, that something has already been done. Your mind does not come and impose its ideas on that voice, saying, "If you do this, perhaps it will be a mistake; don't do that, or something may happen in the future; if you do it… and if you don't do it…" etc. The mind does not interfere. You can rest assured that when you get this kind of vision in your deep meditation, it is correct and it will spontaneously bring its own fulfilment.