Since Moses is presumably the narrator of the stories contained in the Pentateuch, and not Noah, I think you are inadvertently opening a can of worms by resorting to an argument that the main character gave fallible testimony. Using the same methodology, liberal scholars have attacked many other narratives in the Bible in an effort to “demythologize” those accounts and impose naturalistic, materialistic explanations in line with their unbelief.

Consider, for example, the recent claims of one scholar that the Israelites all partook of a hallucinogenic plant while they were in the wilderness. This theory has been advanced to explain the supernatural events that occurred while Moses was on the mountain. That may seem like a fantastic claim to most Christians, but I would submit that it is little different from the assertion that Noah was mistaken about the depth of the flood waters.

After all, a million or so Jews tripping on some naturally occurring drug provides a similarly convenient way to get around what the inspired narrative actually says!