Have you checked that your problem is related to MIME::Lite at all?

The following program shows that you never read the parameters properly:

#!perl
use strict;
use warnings;

my $parameter = 'Hello World';

&SendMail($parameter);
sub SendMail()
{
my $service = @_;

print "Service is: [$service]\n";

my $msgSubject = '$service ';
print "msgSubject is: [$msgSubject]\n";
}
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Single quotes do not interpolate variables.

Parameters need to assigned in subroutines as:

my ($service) = @_;
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