You have to change both of the TransformVector nodes to be from Source - World Space to Destination - Local Space. Just select the node and you will see on the left pane a Source and Destination dropdown menus.
Currently the way you have setup the conversion is, that the transforming of the position now isn’t correct. Basically we want to convert the world position of the static mesh to be the local one, so that the gradients follow the position and the direction of the same static mesh instead. Check out the screenshot bellow for a closer reference. That should fix the issue you have. 
Then you can find the correct direction with R or G (just one of them), since B is typically a vertical gradient.
Let me know how it goes.
