I used to have a bunch of Asus GTX 780 Ti cards with ~91°C VRM temps which I could get down to about ~84°C. What I did was I bought a couple of thermal pads and put them on the VRMs so they were connected to the heatsinks through the pads, because otherwise there were no connection by default. I still think that specific Asus design was faulty.
I had Gigabyte 780 Ti's as well, but while they had no temperature sensor in their VRM, as per a cheap IR gun they were much cooler as they made contact to the heatsink by design.
So if it worries you, based on the design, I would buy some cheap thermal pads to put between the VRM and the heatsink.
You can not believe water is wet, but it's still gonna be that way no matter what you think