Znalazłem rozwiązanie w tym temacie i koduję to:
$cards = DB::select("SELECT
cards.id_card,
cards.hash_card,
cards.`table`,
users.name,
0 as total,
cards.card_status,
cards.created_at as last_update
FROM cards
LEFT JOIN users
ON users.id_user = cards.id_user
WHERE hash_card NOT IN ( SELECT orders.hash_card FROM orders )
UNION
SELECT
cards.id_card,
orders.hash_card,
cards.`table`,
users.name,
sum(orders.quantity*orders.product_price) as total,
cards.card_status,
max(orders.created_at) last_update
FROM menu.orders
LEFT JOIN cards
ON cards.hash_card = orders.hash_card
LEFT JOIN users
ON users.id_user = cards.id_user
GROUP BY hash_card
ORDER BY id_card ASC");