As u may notice or not, it is impossible to use et_Console function to call pb_ rcon commands. Until now it was possible only in etadmin mod, but what i spot the only way to do that is executing a file via function. So i made smth like this:
Do you mean issue pb commands? Its been a while, but I remember using pb commands with et.trap_SendConsoleCommand and et.exec_now without any problems; I'm almost certain I used pb_kick for one.
As for resetting the file, opening it in et.FS_WRITE mode rather than et.FS_APPEND mode will clear the contents each time. I don't think I've ever used it but I would imagine os.remove(filename) would allow you to simply delete the file if that is what you prefer.