From what I see the positioning of those oil coolers further up is for the aerodynamic concept that they are using.
We all know this is a redbull style car with all the cooling and mass closer to the driver, leaving the tail end open for air flow.
Now we may say that those oil coolers don't add much to the tail area if they were in the traditional area behind the engine. However keep in mind that when you move them from that area you are able to use the area for sidepod airflow to take a detour from flowing through the sides and instead over the top of the gearbox.
This concept is purely for allowing the path of cooling air to be shifted upward and towards the centre of the car, out of the way of the rear wheels and floor. This is one of the main reasons for the rear end looking so narrow.
In some ways its a compromise on COG.
The upper roll hope hole is for these oil coolers while the lower one is for the engine intake.