Should My Friend Stop Using His Burner

I have a friend that bully a woman that hurt him, so he publish her phone number in chats and groups. he is doing it for a while, using a burner phone.
It is a phone he only uses for this purpose. Now he stopped, but he want to continue using this phone to browse in the darknet and feel safe. But he knows there was a complaint filed against him in the country where the victim lives and the cyber police there handles it.
Should he continue use this phone? he only use it in public wifis but he is afraid that once he open the phone all the pop ups will come from the apps and the police would know where he is at and come to arrest him, or either check the cctv cameras to try track him?