Ok, I can now concur that there is definitely some other unfound flagging somewhere of whether a visitor will petition besides the meeting information. While I've been able to force visitors to petition who have entered the map without any meeting infromation set, by setting said information, I've now ran into several visitors who would not petition by setting meeting states. I'd assume wherever the flags that control the visitor wanting to leave also house the intent to petition. I know there's got to be some flags SOMEWHERE, but so far I've not been able to find anything based on what is currently in gui/gm-editor.
That said, if the visitor WILL petition at some point, my method will speed up the process.
The gorlak dancer I had made my own using nolimit's method, was no longer in my fort after reloading. Not sure what happened there.
Unfortunately, the fortress I'm testing is getting its 3rd goblin siege, and the weapon/armor break bug has brought this fortress to a close. Unless I exterminate all the goblins coming in, this siege is a guaranteed crash. New fortress started day 1 with rains of elf blood and undead ravens. It's going to be a little bit before I get to a point where I can accept visitors again.