Something odd is happening to the command in the sys-call, and it passed the information back via the exit-code. You might want to consider a slight modification to your routine to capture the return-code and plug it into the string you pass to Die(), don't forget to divide by 256 ....

Something like:

my $return_code = system(...);
if ($return_code) {
    $return_code /= 256;
    Die(... "Return Code from system() was $return_code" ...);
}
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