Potential fix: I zeroed the pivoting oblect to one of the two pivots. Then I created a new object in Blender consisting of a small solid and a socket. The solid was placed in such a way as to be invisible (I am sure there are ways to simply set it to be invisible, but this was quick and dirty using my current knowledge), with the zero at one pivot point and the socket at the other. Then I placed the “invisible pivot” object in one pivot socket of the turret, and the regular pivot object placed in the socket of the invisible one. When I need to rotate one axis, I rotate the invisible pivot around its zero, and when I need to rotate the other, I rotate the regular pivot around its zero. This gives the illusion of the visible pivot having two axes of rotation.