R does not have sufficient force to push the draggable. His finger also has no strength to move the draggable. So join forces.
Excellent puzzle with a satisfying teamplay. Not too hard, but it took me a while to see what needs to be done. Spoiler Took B up first with help from the lower bot, bad idea Thanks for sharing
I found the hint a bit deceptive and the new mechanism seems to require a specific condition. The level of teamwork is not as high as I thought. Entertaining puzzle!