Rtorrent into organizr

I am having some trouble connecting Organizr to rtorrent, where I set up the correct credentials and URL but get “Organizr error” when I try to test the connection. I see in https://docs.organizr.app/books/installation/page/requirements that php7-xmlrpc needs to be installed for connectivity to rtorrent to work, but the Dockerfile for the organizr image doesn’t seem to have it as a package.
Am I doing something wrong or would the image really need to be evolved to support this?

If you’re using our organizr image, I would highly suggest moving to their official image as ours is deprecated and no longer supported (plus still on v1).