Use ~#watch "screen -ls" to monitor any screen sessions starting up and closing. It has a 2 second refresh, so you still may miss it, but it's better than repeating the command. Use CTRL-C to exit the watch.

It' entirely possible that you have the wrong binary on your RPi, and it closes on startup because it doesn't detect the right device.

It's important that you change your "hardware configuration" server side at least twice. Once to something that isn't your hardware type (e.g. select gridseed, if you use zeus), wait 10 minutes, then once back to your hardware. Leave your miners disconnected during this process. Once you have selected your hardware, wait another 10 minutes to be safe, connect your hardware and powercycle the RPi.

The server definitely pushes a different binary when you switch hardware manufacturers. You need to give time for the RPi to pick the commands up from the server and time for the binaries to download. I have no concept of how long it will actually take you to download the binary, so 10 minutes is a safe period.

Are you using a compatible USB2 hub? Try connecting your miner directly to your RPi until it gets picked up and working ok. Further, you need to monitor the power consumption rather than your pool to see if it's mining if you aren't SSH'ed in and looking for screen sessions.