First, thanks for posting.
How do you know the imbalance caused this?
I hope they quit beating it up and zip the skin off to see what the structure looks like underneath. There may be construction errors or a material defect.
Smart People do Stupid things all the time. I know, I've seen me do'em.
RV6 - Builder/Flying
Fiat G.46 -(restoration in progress, if I have enough life left in me)
RV1 - Proud Pilot.