Reassigning variables using submitted_tree vs submitted

So after hours of testing, I figured out how to assign different information to fieldkeys, but the webform php module doesn't seem to work the same way it use to in previous verions

$form_values['submitted'][3] = 'Bob';

$form_values['submitted'][1] = 'Joe';

$form_values['submitted'][2] = $form_values['submitted_tree']['first_name'];

In the above example, I figured out that I can get information from a fieldkey using ['submitted_tree']['fieldkey'], but if I want to assign a new variable to a fieldkey, I have to use ['submitted'][cid], and reference the fieldkey's component ID number... which is cumbersome considering I have over 100 components. Do you guys know a way I can reference the fieldkey with its name when I want to re-assign the information contained in it?