The mayor's 4th order of 30 April 2020 said, in part:
Religious gatherings, including but not limited to, weddings, funerals, memorial services, and wakes, of ten (10) persons inside or ten (10) percent of building occupancy (whichever number is greater) and fifty (50) people outside may resume, provided social distancing is maintained and event organizers maintain a record of attendees. Data obtained by the Department of Public Health, pursuant to this provision, shall, to the extent allowed by law, remain confidential in accordance with professional public health standards and may be used only to address public health concerns.
But now (4 May 2020) it has been superseded and the record of attendees in now only recommended. It is optional now.