That's very small chance to leak and coolant inside is not danger as clear water.
If cooler leak they will replace card because it's very small chance to liquid destroy something...
You see position on AIO cooler.
If you install him on HDD case as someone even if he leak coolant will not drop on hardware.
Graphic card PCB is above possible leak point in case. Tubes look little reinforced for durability.
From pictures look very fine build and nice and they didn't forget backplate.