How to help protester friends organize In Ecuador?

I have friends in Ecuador who are undergoing increasing militarization of the crackdown of protests. They would love something like https://hkmap.live/ in Honk Kong. Is there a way to set something similar up quickly, from existing code for example? Other question, they are using Signal to communicate. Is there a way for members of a group to not be able to see who the other members are (to prevent de-anonymisation by the government)?