gistfile1.php

<?php
    public function getAllUuids($exclude_users)
    {
        $this->uuidOnly = true;

        $this->result = array();
        if (!$this->filters(self::DATABASE_MONGO)) {
            // Searches SQL without mongo.
            $this->loadSQLData(true, true);
        } else {
            // Filters mongo then searches SQL.
            $this->getUsersMongoSQL();
        }

        if (!empty($exclude_users)) {
            $uuids = array_flip($this->result);
            foreach ($exclude_users as $uuid) {
                unset($uuids[$uuid]);
            }
            $this->result = array_keys($uuids);
        }

        return $this->result;
    }

vs

    public function getAllUsersUuids($exclude_uuids = array())
    {
        $this->result = array();
        $this->fields = array();

        // Perform mongo search.
        $this->initMongoCursor(true);

        // Process mongo query.
        $this->processMongoResults(INF);

        // Change uids to uuids.
        $users = ConvertIds::userUidsToWebappUuids(array_keys($this->result));

        $flipped = array_flip($users);
        foreach ($exclude_uuids as $exclude) {
            unset($users[$flipped[$exclude]]);
        }

        // Return the output.
        return $users;
    }