Something different to do is to change his diet, and add supplementation.
ONe of the reasons kids have problems with wetting the bed is due to their diet. Some are just more sensitive than others.
Sugar is usually the culprit. Let me explain why. You know how a drunk can't walk a line if requested. That is because the alcohol turned to a lot of sugar and it effects the muscle control. That is what sugar does, it makes us weak. You might get a big burst but in the end sugar weakens us. Period.
A diet change would be my suggestion. When he eats sugar, or simple carbs, they turn to sugar. Get rid of the treats, or use them very sparingly and in the early part of the day. ( ideally, get rid of it)
I worked with a client years ago, that simply eliminating the icecream after dinner was the trick. OH! and one more thing. B complex vitamin, in a perfect balance, taken at least twice a day. They help a boy metabolise sugar.
Get to the source of why this is happening. Talk with him. By now, he might be willing to make some changes in what he eats, if he knew it could be possible to stop wetting the bed. and make a reasonable amount of time commitment to the process. If it doesn't work the first time, don't throw the baby out with the bathwater, work at a diet rich in veggies, and protein, and even limit the amount of fruit. He might just be a bit more sensitive than most to sugar.
One more thing, the sugar could make him so tired that he can't wake up.
Big spirt of energy and then complete exhaustion. When he is sleeping he is in the complete relaxed muscles, "coma" like sleep ( again, much like a drunk... they party hardy and then pass out)
Let me know if you need any help in selecting the perfect supplement for his needs.