All of the ball links were stiff. He got the ready-to-fly combo, and nowhere did ti mention that the links need to be individually adjusted. You could have put two quarters on a paddle and the head would not tip. We got out the pliers and gently squeezed each socket (with the bal inside). Then test the fit. If still too tight, repeat, squeezing in a slightly different place on the socket.
This is easier to do with the head disassembled, and just working on individual joints. We were doing this on his assembled heli, so it was difficult to determine if any joint was loose enough becuase all of the rest of the joints were stiff too. But we got it better. He had set the throws on his servos way up to try to get any response out of the cyclic controls. I am sure that after he gets all of the joints adjusted, he will want to set the throws back.
We also put his heli up on my turntable so that we could test his gyro and mixing without worrying about flying it.