I haven't had this problem in the past but I'm trying to retrieve a field value in a Views PHP Field for a view I made for Search API. I'm using the code below but I tried with 'nid' as well.
$stream = $data->_field_data['vid']['entity']->field_stream['und'][0]['value'];
You can see the var output here. I'm trying to get field_stream but am having no luck...
http://www.ovwrc.com/waste-search?search_api_views_fulltext=poop%20poop