The answer would be no. Let me explain a bit. The 3rd and 4th guest rate is based on people in the same cabin. It is a discount to utilize upper berth capacity.
If you have two connecting cabins, each cabin will need to have 2 full price occupants. Then the 3rd and 4th are discounted.
This is as far as pricing, if you want to adjust sleeping arrangements is ok.
Hope this helps,