I feel like I was sent to this site today to answer your bedwetting questions. (I’ve never been here before, and I doubt I’ll be back)
Your boys probably do not have a bladder problem or anything that can be solved by limiting fluid, getting them up at night, etc, etc. I tried all the same things that you did. What I learned about bedwetting is that in most cases it is a sleep disorder. Your boys are simply sleeping so hard they never go through an appropriate REM cycle. I bet when you get them up in the middle of the night it’s like they are zombies, or sleepwalkers – they probably don’t even remember it the next morning.
I paid Thousands of dollars to help my son. But I’ll get you started and hopefully with persistence on your part you can accomplish the same thing for little cost. (you might want to do this one boy at a time or you may not get any sleep yourself) Buy a bedwetting alarm (loud) & stop using the pull ups. When the alarm goes off YOU have to wake your son up & make HIM turn off the alarm. Make him change his bed, reset the alarm and go back to bed. This will help him reset his sleep cycle. Use whatever means necessary (no child abuse allowed) to wake him. We always found that an ice cold wet wash cloth on the face or back did the trick, but you can find other helpful hints on the web I’m sure.
Some more tips
The best type of alarm is one that lays flat on the bed. Have your son(s) sleep naked on top of it.
Never punish or belittle your sons. It’s not their fault. Do have them accept responsibility for the mess it makes.
Keep a diary and celebrate accomplishments – 1st dry night, 1st dry week, etc. Don’t make a big deal about slip ups.
Protect the mattress and keep plenty of clean dry sheets available for use.
Teach your kids how to wash their own sheets. Make them responsible (don’t make it a punishment though)
This is not a quick fix. It may take several months for this to completely work. (My son was 13 and it took 5 months)Others I’ve given this advise to have had quicker results. Each child is different. BE CONSISTENT AND PERSISTENT.
I used to be on the board of a non-profit called Dry Kid Acadamy. I haven’t been involved with them in years, but their website is drykid.org If my suggestions aren’t working contact them.
Best of Luck