Share a Volunteer Signup Without Sharing Contact Details
Give people a Proximatic link showing jobs, hours and open places. They can choose work while organizers keep the contact list they need to run the event.
Give your community group an invitation it can pass along. It doesn't need the spreadsheet containing your volunteers' email addresses to help you fill the crew.
A public Proximatic event link shows the jobs, hours and available places. Volunteers can choose an open shift and sign up with their name and email. Your authorized organizers get those commitments on the event roster; the public invitation doesn't hand out the contact list.
That lets a library, school or neighborhood group share the same useful page. If the welcome desk fills, people opening it later can choose other work. You aren't sending updated copies of a response sheet into several groups just to show what's still available.
Keep any existing form's response-sharing settings separate from its invitation. Google's sharing guide explains the options. For the event itself, share the signup page and keep running the crew from your organizer view.