Yes, amazons might not be the best char to go for bosses like them, but they can certainly be of use.
With the lighting tree, you can kill everything that is crowded and not lighting imune. In combination with a good tank, they can certainly help.
With jab, you can deliver very fast crusing blows, which is very good for killing übers. I think people has done it with a jaberzon, solo.
The only zon that has a very tough time there is the bowazon. She is only as strong as her tank, and not many minions can tank there. Though with a char that can, the bowazon can be of use. She has a quite good crowd control, if you use the good skills.
And besides that, I think an amazon using the bow skills as her main attack most be capable of soloing the übers, just don't know how. Sorcerors do it with mostly elemental damage, and strave can deliver fast crushing blows. It might be nerved, but not many char has a 8/2 frame attack I think. Just my idea, still need to find someone to put it in a build.