Looks like you need to add 'option' to your footer the_sub_field() calls:
<p><a href="https://wordpress.stackexchange.com/questions/307577/<?php the_sub_field("footer_link', 'option'); ?>"><?php the_sub_field('footer_link_name', 'option'); ?></a></p>
var_dump() is used to dump a variable, not a string, so you would need to do something like var_dump($test) for that line to work. You are probably getting errors and warnings in your PHP log files – if not, you could turn on WP Debug to help figure out which lines of code are causing issues.