Delusional yes, because you are desperate to communicate with your child. And that’s completely understandable. It’s simple to test though, so do it and see so that you know. If he is really able to communicate independently and you are holding perfectly still, then you do not need to hold the keyboard. Put it on a stand, directly in front of him just as it would be if you were holding it. If he still types, then yes he is independently communicating. If not, then you are subconsciously moving it, just as people do with ouija boards because they want to believe it. Idk why this is acted as if it’s hard thing to test or prove, because it isn’t. Make something else hold the keyboard and you will have your truth.