Yes, jellies are weak to the crush attack. So using weapons like the abyssal bludgeon or inquisitor's mace is going to be extra effective here. However, you do not need to go out of your way to buy these weapons just to kill these monsters.  You will notice that their defense is almost unexciting. You can use any melee or ranging weapon you want here. If you do not know what to bring, and you do not have an extremely strong crush weapon, just use your best melee or ranging weapon.