There isn't any such thing as night time potty training. Either he's dry in the morning every morning or his body isn't ready. If he's waking up wet then his body isn't ready.
Night time peeing isn't in his scope to stop. He goes to sleep, his body shuts down and he's not supposed to wake up to go pee. Actually if he's waking up to pee at night then he could have something wrong.
Limiting his drinks makes things worse too. Of course we're not going to give our kids a gallon of chocolate milk at bedtime and expect them to stay dry but normal drinks at dinner and some afterwards is pretty normal.
His bladder is supposed to stop/reduce production of urine when he goes to sleep. This is why everyone is able to sleep through the night. Our body gets a signal from our brain to sleep and many things change. Our brain takes all that excess energy/activity/excess ability to work on other things. Such as fighting off disease, repairing injuries, working through stressful problems (dreams), and more.
He should be going to bed and going to sleep and staying dry every morning for weeks and weeks before he's "night time" dry. It's not up to him or you when that happens. It's a stage of development.
Like....walking. You can decide a 5 month old baby is going to learn to walk. You can work at it and work at it but chances are that baby isn't going to have the developmental skills to walk until they're older. Then they'll walk on their own. Same with peeing at night or even pooping. If they are doing either one while sleeping then their body/brain hasn't reached that stage.
During the day time when they're awake they feel the urine or feces pressure and know but when their sleeping???? Their body is under the influence of their brain and there isn't anything a person can do to their brain to make it develop any quicker.