Don't think you can with 4G connection, you can try to google about it. Again if he gets stuck and can't move but he still hear in-game music etc. then most likely his MAC address is formatted wrong. Just tell him to click "Change MAC address" and it will randomly generate a new one, correct format is something like A2:CC:9E:73:1B:26 and NOT A2-CC-9E-73-1B-26 or A2.CC.9E.73.1B.26 there must be colon between each, no hyphens or periods. Double check that when the game is running because some people use "Game configs" which will change settings when you boot up a game.
If he just get stuck and it looks like the game froze, if he waits about 10-15s it should pop up "Communication error has occurred" which just means the connection to that IP failed.
If he just get stuck and it looks like the game froze, if he waits about 10-15s it should pop up "Communication error has occurred" which just means the connection to that IP failed.