If the DLC can't release because of the problem's with the RAM system of the PS3, why don't you release it on a small parts?
To me, the only thing i wait to this DLC, it's the vampire lord form. New Quest, new faction, new map, i don't care about but the vampire lord form is important for all PS3 users who have a save with a vampire. (i think players with werewolf or not don't care about of the vampire lord form)
So, why don't you release only the part with Serana and Harkon to gain the vampire lord form (and maybe the quest with if it work)? And later if the PS3 can acquire more DLC, you release the Dawnguard fortress (and maybe the quest if it work)? And more later, if all work, you release the other part of the Dawnguard DLC.
But, like this, the PS3 users can download only what he need (and what he can). If someone want only the vampire lord form, he can. If he want only the Dawnguard, he can. If he want the vampire lord and the new map, he can. If he want the Dawnguard and the new map, he can.
And if he downloads all of the DLC and the PS3 bug, it was his choice, not yours. But if he downloads all of the DLC and the PS3 doesn't bug, it was his choice too.
Personally I'd like to have the Dragonbone Weapons, Crossbows, Arrow Crafting and The "Face Sculptor" in Riften and of course the Vampire Lord and the new Werewolf skill trees.