Actually no idea if it would fit a 980Ti, but it is a very simple cooler, and given that board the only concern would be the height of capacitors at the rear of the board. And any GPU from that era would have had a similar design.
Nvidia hasn't changed the size of their mounting holes on the larger cards in quite some time. And it has no direct contact with the memory, so that should still be fine.
The fans are ludicrous though, you could pick out some nice RGB LED fans and use those instead. I don't think it would be any better than another Axial cooled heatsink like Zotacs or EVGA's ACX2.0.
That is another option, you could strip the shroud away from the cooler you have and put your own fans on there.
You are really delving into custom territory at this point.