What Uriel needed more than anything right now was to keep everything he could a secret to remain safe until he made sense of things. He also needed to understand his new found power, if there was any to begin with. The last thing he remembered before waking up at the hospital, was Water warlock stating he wasn't a worthy candidate to bear his blessing so he wasn't sure of what had actually happened. All he knew was that he was now able to regenerate.
There was also the need for a hideout, in case he needed to disappear for a while. Maybe Nika's suspicions were unfounded, but Uriel couldn't deny the possibility of being targeted by the Mapple corporation in the future if they found out the truth about what really happened in Chichén Itzá and that, not only did he use the dagger, but also kept the clay figurine for himself.
All of those things would only be possible if he had a place of his own.
