Getting value from drop down for in place editor

I have a drop down of countries. When a person selects a country, a
second drop down of cities that are located in that country is
populated. Beside the city drop down, I have the word “New” which when
the user clicks on, turns into an edit box where they can type in a new
city for that country. When the save button is pressed, it makes a
backend call to my action. Since in the action, I am creating a new city
for a country, I need to know which country was selected in the first
drop down.

How do I pass the country ID for the selected country into the action?
It looks like the in place editor makes its own little form, and when
you submit only a couple of things in that form gets submitted - one
being the value you type in the edit box.

Thanks for the help