Personhood implies social responsibility.
This is much more than paying taxes, it involves a wide range of social interactions including employment, self-reliance, participation in government etc.
Chimps if "released" could not function in our society. Releasing them into the wild would be a death sentence for most lab animals.
They would still need to be cared for, and are unlikely to be able to contribute much.
I do not see how a judge could make a finding of personhood under (what little I know of) American law.