I highly doubt they would take just Cogat. There is still a fairly large difference between an IQ test and CoGat. Cogat will not tell you anything about the child's actual IQ level. The best it indicates is that if your child has high scores, it is a safe bet the child is gifted at some level.
Does Davidson still do a portfolio acceptance?
If so, you might be able to try that.
On the verbal...the question I would ask your son is if they read the questions to him, or had him read the questions. They often do read the questions out loud at the very early grades.
Kids that are not as strong with their audio skills I expect would actually have depressed verbal scores. I saw this with my kids. One child told me she had one wrong, because she thought the person said penguin and she put pencil. It isn't that she didn't know the answers, but that she misunderstood what was said.
