Are you sure you did compile the script first? As it seems to be missing several binaries (all these "can't exec ./balahblah, not tested")

You need to do a "make sense" in chkroot's dir (Its explained in the README).
With these binaries available it will probably give some more hints, if there is really a rootkit installed.

Plus, are you running something like portsentry? Because this might also cause this
bindshell alert...