I’m not familiar with RBG so couldn’t comment one way or the other on how it compares to other greases.
The clocks seemed to run fine after letting the movement run without the escapement
so that makes me think that there may be dry spots as well as excessive build up in places as the grease may not have spread over the springs entire width and length. This will cause sticking and slipping of the spring. If you haven’t already you might want to try winding and letting the mainspring down a few times before running the clock. This will spread the grease uniformly over the springs entire length and width. My guess is that this will take care of the problem. It’s also a necessary step when lubricating mainsprings in watches.
Hope this helps Wingman,