Getting "elected" is the easy part. After interrogating enough outsiders to understand what it means, she just persuades her brother and mother and closest friends, to "vote" that she should go to the convention. Anyone else who wants to vote can, of course, but nobody else wants to go and nobody else cares about whatever crazy outsider-related idea Liushna has now.
The hard part is persuading her rokoa to let her go.
"Please?"
"You will get killed."
"I probably won't!"
"You will get killed, and your bones will lie far from home, and nobody will know where to find them."
"But if it works--"
"No."
And if the rokoa had her way, that would be the end of it.
But Liushna doesn't give up that easily.
Finally the rokoa gives up and gives her permission. It isn't lost on her, of course, that Liushna could simply have disobeyed her and left on her own. It would have risked her being cast out of the clan, but Liushna is a reckless youngster, and the rokoa wouldn't have entirely put it past her.
But Liushna is a good kid, and she loves her tribe and their traditions, and she would have stayed if the rokoa had stayed firm.
If Liushna is wrong and she never comes back, the humans will pay in so much blood.