I have read your post and I was all set to be on your side, but your son is 20. I think you both need to met in the middle here. I know from my watching my husband and son that your compensating for dad being so harsh and controlling isn’t helping your son either. ADHD is an explanation for behaviors not a reason to not take responsibility for them. When you catch your son in a lie does the why really matter anymore? He needs to know it won’t be tolerated and that consequences exist. As for timeliness he needs to find tools or a method that works for him and he needs to follow through. Unless you are planning to be his brain forever he needs to develop these skills. Life is great at teaching these lessons if you just let it happen.