Maybe that proposed Secret Stream singaround has been withdrawn. I didn't take any note of the day or time or who was leading the session. Today I don't see it on the Camp Harmony schedule https://docs.google.com/spreadsheets/d/12jldcYY9h_brhNvp-A9HZP6cusmaSIDmOhW9NFUrdhI/edit#gid=169893150

Of course songs featured in the book would feature at other singarounds.
Camp Harmony is online from 30 Dec - 2 Jan 2021-22. Pre-registration is required and that closes at noon- US Pacific time (2 pm Central, 3 pm Eastern, 8 pm GMT, etc) - on TUES 28 DEC. at https://forms.gle/DPuWTC5FAe3a7crWA