You've already chosen an answer, but I think you're making this more complex than you need to.

A lot of people have the same names as famous people, whether by choice or accident. You don't see the estates of famous people demanding average people change their names to avoid confusion, and there's no reason you should worry about it unless you are explicitly trying to imply that your NPC "Goerge Bush" is somehow supposed to be the real one. And even then, even if it was satire, you can still use the real name.

Seriously, just a simple disclaimer like was posted in another question and you're fine.

"All characters appearing in this work are fictitious and randomly generated. Any resemblance to real persons, living or dead, is purely coincidental."

You've already chosen an answer, but I think you're making this more complex than you need to.

A lot of people have the same names as famous people, whether by choice or accident. You don't see the estates of famous people demanding average people change their names to avoid confusion, and there's no reason you should worry about it unless you are explicitly trying to imply that your NPC "Goerge Bush" is somehow supposed to be the real one. And even then, even if it was satire, you can still use the real name.

Seriously, just a simple disclaimer like was posted in another answer and you're fine.

"All characters appearing in this work are fictitious and randomly generated. Any resemblance to real persons, living or dead, is purely coincidental."