Trying to add get_the_title hook to this line

Joe, have you tried

....placeholder="I am interested in: '.get_the_title().' "....

also you don’t need all those php’s. The code can be cleaner, easier to read. One can do either:

<?php 
echo '<form action="' . esc_url( $_SERVER['REQUEST_URI'] ) . '" method="post">';
echo '<h5>';
echo 'Ask a question <br/>';
?>

etc

or

<form action="<?php echo esc_url( $_SERVER['REQUEST_URI'] );>" method="post">
<h5>Ask a question </h5>