This thread is a spinoff of the 12" storage thread.
It appears that I am not the only one who got their weak material figures warped during storage.
I repaired my battle droids by tying their legs to rigid lengths of metal, tight enough to straighten the limbs, then allowing them to get hot and then cooling them. I used full lengths of tungsten from "TIG" welding. But as they are extremely expensive I do not suggest to everyone to go buy them. On the other hand, there is cheap tungsten you can get, but it is still fairly specialized and may not be easy for everyone to find. I have also used simple objects like pencils with perfectly acceptable results. I tie the limbs to them with twist ties so that I can apply more or less force to the area being straightened as is needed.
I never opened a Geonosian Warrior, so I have ti hope for help from others who may have had and been able to fix the problem with them.