I have my thoughts, but given this is a hypothetical situation, it's not worth expressing them, since the OP can change things around at will, and we'll end up chasing our tales. Sorry - but IMHO, this is a total waste of time.
So, say the Coyote and the Roadrunner were holding Porky-pig hostage.
Would the document Tweety signed still be binding even though Sylvester threatened to shave off Yosemite Sams mustache?
Only if signed with a pen from Acme Co.
But what if space aliens!?
yeah, but is he the fastest in the Pecos?
yeah, but is he the fastest in the Pecos?
No. That would be me.
If you have to write something, don't sign your actual name, sign it "Under Duress". Better yet, don't sign at all.
I sign all of my traffic tickets that way. Never tried to argue it in court, though!
Oh, I know. I always wondered how far someone could argue they were under duress to sign it since the only other option is imprisonment. I always wheel and deal with the prosecutor before it gets that far.