Thats very interesting. But from a humorous point of view can you imagine someone taking a deficating donkey into the church and saying its only natural?
This dream to me illustrates how we dont have all our faculties when we are in the dream state. Could he not have untied himself or got help? Yet, if we are overly skeptical we could miss out on the meaning of this dream and what God wants to tell us through it. Obviously this saint thought that God can speak to us through our dreams.
Perhaps the op can ask God to show him what these dreams mean.
It might seem confusing to us that something when done awake is a serious sin but when asleep is no longer a sin. I think when it comes to our sexuality we can learn from this that none of the natural actions of our bodies are sinful that occur during masturbation, for they are all natural to the way God made us. It is the intent that is sinful. For instance, Something done outside of marriage may be sinful but inside marriage it is not. Yet, it is the same act.
Thus, the same act done asleep vs awake can be interpreted differently since the intention is different. When someone is asleep their will is weakened. When that same person is awake their will may be strong. The difference is being asleep. it is something beyond their control. And without control, without the ability to make free choices how can it be sin? How can one be accountable for something they have little or no control over? Thus the will of the person when awake is what counts.