Luckily I have only limited experience with laminitis...Arabs have awesome feet...but a couple question come to mind from what I do remember from the couple of times that I have dealt with it...What is the surface that he spends most of his time on? I know with my one mare that did come down with it, we had to keep her in a stall with thick sawdust shavings and sand to lessen the pressure on that hoof. Also we were encouraged to get her to lay down as much as possible again to take the pressure off the foot. Naturally we couldn't leave her down all the time, so we would walk her daily but let her go down as long as she was resting comfortably.
Is he on any fluids or antibotics? I don't remember off hand what we were given for her but I do remember having to keep her on antibotics and also constantly checking the foot to make sure she didn't have any absesses that needs draining. I also had to have her shoed with corrective shoes while she was lame, whereas normally my arabs all ran barefoot. As well as giving her fluids for awhile.
The only other thing I can think of is if you have the ability to do it, is setting him up in a stall in a belly sling so he can be up but not putting weight on the bad leg.
Sure hope you can get the little guy well and not have to put him down...I'll be saying extra prayers for him.
Mel, Maxwell, Musette & The Fur Gang