Even if there were members of the Luo Clan that weren't present in the Luo Clan's land, Deus could kill the Luo Clan members without having to worry about the backlash since Real Delusion would cover it for him.
And besides, even if the government knew about the extermination of the Luo Clan in public, they wouldn't make too much trouble with Real Delusion since the government knew the consequences of offending Real Delusion.
The government wouldn't protect one clan from Real Delusion. Instead, it was more likely for them to coerce Real Delusion into sharing a few of the assets of the Luo Clan and in return, the government would keep quiet about the incident of the Luo Clan's extermination.
That was why Deus handed all of the rights of the Luo Clan's assets as a tribute to Real Delusion so that Real Delusion would deal with the bribes for the government. He only cared about the extermination of the Luo Clan rather than their assets.