Your problem is probably in your split, and then cascading from there.

@ARGV = split(/ \\\\/, $Line);
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The key you're trying to split on (' \\') probably doesn't exist on your line. That will cause the entire line to be put into $ARGV[0]. Then you shift the only item in @ARGV out into $DisplayName.

$DisplayName = shift @ARGV || die;
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Then you attempt a second shift

$Machine = Win32::NodeName() unless( $Machine = shift @ARGV );
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This of course will fail since you've already wiped out @ARGV. This causes Win32::NodeName() to return the hostname of the current machine. Finally you attempt to build a UNC path.

$Machine = "\\\\$Machine";
$Machine =~ s/^\\{2,}/\\\\/;
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Win32::Service::GetServices() requires a hostname, not a UNC path. So what you end up feeding Win32::Service::GetServices() is a host name with two backslashes it. This causes it to fail, and windows generates the "The RPC server is unavailable" error.