I’d first make sure the binary is the latest version available from Amazon.
Check to see if you can execute it manually. If you need some source material to work with, the command can take epub files.
I would not expect a SIGKILL (assuming that is what they mean by “Killed: 9”) to occur for this reason, but while you’re on the command-line run an ls -l and make sure the executable bit is set. Some unzippers fumble on UNIX permissions.