In theory, this should work...but it doesn't.

#! perl -slw
use strict;
use Encode;
use Devel::Peek;
use Win32::API::Prototype;

ApiLink( 'advapi32', q[
    DWORD QueryUsersOnEncryptedFile(
        LPCWSTR lpFileName,
        ULONG pUsers
    )
]) or die $^E;

my $buffer = chr(0) x 4;
print Dump( $buffer );
my $pointer = unpack 'L!', pack 'P', $buffer;

printf "%08x\n", $pointer;

my $uFile = encode( 'UTF-16LE', $_ = $ARGV[ 0 ], 1 );
print $uFile;

QueryUsersOnEncryptedFile(
    $uFile,
    $pointer
) or die "$! : $^E";

print Dump( \$buffer );
print unpack 'C*',$buffer;
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