print $csv "$lpname\n";
        print $csv '*' x length($lpname),"\n";

            print $csv "$i,\n";

    print $csv "\n\nHost,Entitled CPU and RAM as of @asof,\n\n";
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$csv is not a valid FILEHANDLE. It has not been opened anywhere so it cannot be printed to.

        open (my $i, "+<", $name) or warn $!;   ### FAILS HERE ###
        while (<$i>) {
            chomp $i;
            next if $i =~ /$regexp_2_skip/;
            next if $i !~ /$regexp_2_get/;
            ($i) =~ s/:/,/g;
            ($i) =~ s/\s+//g;
            print $csv "$i,\n";
            print "$i,\n";
        }
[download]

The variable $i is first used as a FILEHANDLE and then used as text from a file. But in the line while (<$i>) { you are assigning the file text to the variable $_ which you don't use at all.