@Sistah Sleuth: 100 points for humor. However, for the same reasons, I can't put Manorville and GB in one pot, I can't put AC and GB in one pot. Behavioral patterns which would be hard to overcome, if at all. Having said that, there are some minor similarities and it wouldn't make me wonder, if we find one day, LISK and AC share one or two of the secondary diagnoses.
Well, lets take a risk, because I have now to include two highly political incorrect terms: Ethnics and religion. Hopefully, I will not get banned for it.
First take a look at the staging in AC:
Face down, no shoes but otherwise wearing clothes, faces turned to the East.
Burying someone face down is in many cultures a sign of disgust for things, the dead did during lifetimes. Rarely, it is also a protection measure against upset spirits who may come back to haunt someone, who believes the spirit of this dead person has maybe a reason to take revenge - e.g. for killing the person buried.
Face east and no shoes is something, you find in some Islamic cults. Normally Islamic burial tradition demands, that nothing goes in the ground that can't decompose. That is the reason, that the dead normally wear light leather sandals or just linen shoes when buried. Some variants of Islam include simply socks but no shoes. And east isn't only the direction to the casinos of AC but also the traditional direction to Mecca ... well, this comes from the time, nobody had really figured the world is round, so it's ritualistic always east.
Another detail points in the same direction. The arms were straight at the sides. Western/Christian burial traditions would put the hands/arms crossed over the chest. But that's a hard one, because the bodies were staged face down.
All together: This has all the hallmarks of an Islamic burial staged to express disgust beyond death. Which isn't too surprising at all, because all the victims were prostitutes, which are seen in Islam as in Christianity as equal evil. But it is at the same time a sure sign of a (negative) relation with the victim beyond death. This negative relation is the justification for what the AC-killer does and therefore, it would be hard for him, not to stage. In itself, the staging is kind of a statement.
Now Gilgo Beach:
The phone calls were taunting but also justification if the tids and bits, we got, are correct. In fact, the justification part of the message is a little similar, because it concentrates on the generic accusation of being a "*advertiser censored*" and gives quickly room for sexual fantasies. This a little cramped relation to sexuality is in itself pretty Christian, other cultures don't have such big problems with the subject.
Now look at the victimology. Four women, all looking caucasian but otherwise different. They were just naked as they were at the time of the killing. And their bodies were dropped just out of sight. That's a killer, who has no relationship beyond death with his victims. He doesn't feel bound to do anything to use the bodies as statement. If you study a lot of cases, you will find, it's pretty rare that sexual driven SKs have no special visual type of victim. Ridgway, the Green River Killer, is such a case. But typically, those rare non-typed sexual predators also change ethnicity of the victims just for the sake change. Psychologically, they explore differences in how it feels. Now, LISK2 didn't do that. Which makes the whole picture a lot more similar to some serial rapists than to other SKs. There were already some SRs who stuck in one victimology but no definable optical type of victim. The Waldo-Rapist is at least here where I am, the best known case. It's a cross over between over-compensator for some deep sitting feeling of inferiority and anger-assault-rapist. Regularly those perpetrators are African-American and pick exclusively white women to assure their dominance in forced sexual acts establishing the usual over-compensation of the typical NPD patient. In a psychological way, it's the instrumentation of a defense mechanism called "splitting"
So, sorry, no way, that is one and the same guy.