You can only use five cards, to use the A as the highest kicker would mean you have six cards. Your hand is a straight and to make a straight you have to use five cards. The only possibility of not splitting this pot would be if you had QK because then you would have the higher straight, from 9 to K.
Top five cards make the winning hand. Everyone who has a Queen in their hand can use 4 cards on the table, J, Ten, Nine, Eight to share the pot.
This would have been a dangerous hand in omaha, because you can only use 3 cards on the table and 2 cards from your hand. So the qj would hope not to run into a kq
is a ladder not there kicker all have a ladder with the same cards because the pot is divided the kickers are for high cards parstes and even poker failing
At Hold'em you have to make the best possible hand using any combination between your two house cards and the five common ones on the board. So you can use one or both of your cards, or even none, to form the best combination possible.