all the info seems to be correct except for the 20 minute spawn bit... its actually a 30 minute spawn. I've killed just that spawn about 18 times sofar and have gotten Shoqui twice.
This guy seems to be a 1 in 5 spawn on a 20 minute timer. Ring is uncommon and leggings are common.
Can't be snared or rooted, can be slowed.
If you are in the doorway looking into Ralo's room he spawns directly to the right next to the doorway in the room. His PH is an undead troll that doesn't cast. If you don't lull and just pull him right away before clearing the room you'll get 3 adds.
I should note that casters can spawn in the room and love to buff the mobs around so sometimes they will have SoW, haste, resist buffs. Druid got annilated when she tried to pull him and they all ran at sow speed right at her. If you can slow him (took me til the 4th try to land slow, my guess is he had a MR buff off some kind) he goes done easily. He does not cast but other mobs can making FD splitting a risky business.
The one time we saw him up was in the treasure room below deck next to Ralo The Black. Dropped the Ring of the Sea. Hes probably pretty rare, as we've cleared the treasure room several times and never saw him pop. Just happened to be up when we arrived one day.
I killed him many times... Dropped Ring of the Sea (All/All) and Hideous Chain Leggings (All/ Rng-Rog-Shm). The leggings arent that great but the ring sold for 20k on bertoxx. Its a nice EB item to have.