A good backup for matching notes to syllables if you think your ear is missing a bit of awkwardness is somebody else's ear. I can't think of anything else that would be as reliable, but you'll still wonder if the other person's ear is off. (Is this the "Van Gogh Syndrome?") I guess you'd want to ask more than one person, or find someone you know is rhytmically savvy.

Your idea about asking your Dad to read the lyrics aloud is a good one. You'd figure out what was causing the problem and it may give you some insight into how he hears written words in his head.

Feel free to consider me an alternate ear if you should want one. I'd be happy to share my opinions. (Why do I think I probably didn't need to tell you that?)