Anyways, the error that we are getting is that someone will lose connection mid game. Then, even though they are green, they can't see anyone else in game. They can't reconnect to a new game (any new game won't show up in the LAN menu) or find anyone else. Only when they do a restart of the software are they then able to see other users / matches in game.
Does anyone have any idea what may be causing this issue?
Could you send a screenshots of pinging in both directions when this problem appears again? And Radmin VPN logs Radmin VPN - Help - View log
Check if there is no programs that overload your network, like FTP, torrents of Windows updates.