6 years later, time to make a relevant post
(just because it’s the first Thread I came across on my search)
You can do it easier and more stable this way:
Just use the same Rotator node and in the details panel, make sure that the second rotate node has it’s rotation center at [ 0.0 , 0.0 ] and plugin your rotation value multiplied by -1.0. Also the rotation speed of both Rotator nodes should be the same.