Yes, you can. See my post I made on lemmy.world - showing up in the feed of @fediverse@lemmy.world using my mastodon.social account (in the mastodon app). For that to work you have to have the community address and look for it via the search on the mastodon instance.
Screenshot is made in the mastodon instance.
Very interesting, do you have any source or references that springs to your mind? I have emergency SOS enabled, but it never happened to me that it has been falsely triggered. And I can’t imagine many scenarios were it would be.