I had this same issue - the players I wanted to connect to were only visible from my main/admin account on my iPhone and not for a home user attached to this account. During troubleshooting, I discovered this was only an issue on wifi. All players were there for the home user when connecting from a desktop via ethernet.
I disabled “Multicast-to-Unicast Conversion” on my wireless access points and now I can see all players from my phone using the admin or home user. So thanks to elan for mentioning the broadcast UDP requirement. Hopefully this helps someone else having the same issue.
I haven’t been home since my post, but will be looking into it during the week. Is there a safe way to send the logs, I don’t feel safe posting these logs on an open forum like this