I think that gliders nails are too small and fine and that with how fast the dremmels can go (and yes, I know you can make them go slower, but I think even then there is way too much of a risk) that you could easily mangle a glider's finger and/or hand if they suddenly flinched or pushed toward the dremmel when you weren't expecting it.
The cover is still very large and the smallest hole is not tiny, not to mention the space between the cover and the actual sanding band. I think you would have to hold the glider's finger inside the attachment to get the nail close enough to the band to work. I also find (I have small dogs) that it is difficult to maneuver the nail so that I can grind it off an the correct angle, which would also be needed on the gliders (which I would be afraid would expose the pad much to closely to the band).
Even on the most calm, laid back glider, I would be worried about what might happen. Their nails are just so close to the tender pads of their fingers, I would not risk something like that.