I'm not still sure about it but think there are three teams that will get to the World Cup and these teams as you said but a better chance however the only thing they have in Saudi Arabia is money and they still don't have strong teams like Australia and Japan while I think Japand and Australia are both in the better situation to get themselves other first two places of the table. Australia and Japan are two teams that were usually in the World Cup from Asia.
No doubt in current situation we are having Saudi Arab as one of the weakest side in top rankings because Japan, Iran, Korea and Australia are having much better teams, and they can take good advantage of their quality and consistency, but things are also going good in Saudi Arab as they are doing their best on domestic level.
We are having the biggest issue with conditions and domestic level is needed good overhaul which is not easy but still as they are investing and having their long run vision we can expect they will be brought their best in coming years and things will be completely change.
Now we have 2 years in world cup and most chances we will be having these teams into this event with Qatar and Saudi Arab are coming being these teams, and they are having challenging matches due to improved structure in few big countries which is important for the development of the game.