Chat customization for Non-Profit Counseling using Open Source

I am working with a faith-based Non- Profit that is wanting to launch a counseling type platform to offer FREE help to broken people in crisis. We believe a crisis of faith and our spiritual relationship with God is essential today. I need to customize or modify the ideal Open Source Chat app that can offer users anonymous chat, (text and chat only, no audio or video needed). We also won't need fundraising, or donor management functionality. I would like to explain feature/functionality in an interview but can attach requirements. An Initial filtering intelligence would be needed from scanning the "title" and "comments" fields for directing the user to the ideal "responders/counselors". If additional help is requested or ongoing, chat dashboards need to allow counserlors to create critical notes for review and preparation for the next meeting. All requirements of Features, Functionalities and dependencies with VISUALS can be seen in the attachment. Other needed features within a Chat Platform: • Minimal scheduling for future sessions • Something basic to support an online donation, but we don't ask or request, or solicit • Update an easy to search and filter contact database • Easy internal member communication and dialogue when asking help for a unique problem in a current conversation • Can support between 2-500 responders • Can manage Time Zones • Can populate "chat field" with outside API resources like—Stats, links, pdfs and quotes that are vital for our ability to offer meaningful help. I already have a number of links to public domain software. • Basic analytics and reports (within requirements) Riot, Zulip, [login to view URL], Mattermost, Wire, Wild Apricot, and any others you have familiarity on is fine for us to consider. Even if it means just creating Chat functionality since our purpose is so specific to our unique needs is fine as well. I have a link to a current NPO chat app I can share once we interview. Ministries, where this has currently being demonstrated but for different purposes are: [login to view URL] Thanks very much for your consideration. There are many broken or overtaken by their appetites and needing help. I am needing this done ASAP. -steve