I looked at the manual online
From the photos it appears the stabilizer is stick built so it could have some bad glue joints.
http://media.hobbypeople.net/manual/123771.pdf
Page 41 mentions sealing hinge gaps. Is that done?
Page 43 mentions the tail bracing but doesn’t go into any detail.

Based on the balance issue post, it does make you think it could be a wreck. This is an ARF and it’s designed to have the elevator servos in the tail. You shouldn’t have to redesign the control system and move the servos up front to balance an ARF. The RCU Magazine review discussed balancing and didn’t report a problem.