You can't add arbitrary values to a dropdown once the form page has loaded. The form digest will only aloow you to select values which existed when the page originally loaded.
Also, because you are adding options from a different Site Collection (as indicated by your URLs), the IDs for the options aren't necessarily going to match any current value IDs.
M.
Also, because you are adding options from a different Site Collection (as indicated by your URLs), the IDs for the options aren't necessarily going to match any current value IDs.
M.