shortcode capture not working.

Hey,

I am trying to populate an option dropdown based on an array generated from a shortcode. The shortcode is an official InfusionWP code. Currently the code looks like this:

ob_start();
//    echo '1234, 4321, 5678, 8765';
  echo '[i4w_db__HalifaxonlineAcNumber]';
  $accno = ob_get_contents();
ob_end_clean();
$clean = str_replace(" ", "", $accno);
echo '$clean: ' . gettype($clean) . '= '.$clean.'<br />';
$exploded = explode(",",$clean);
echo '$exploded: ' . gettype($exploded) . '= ' .$exploded. '<br />';
print_r($exploded);

to wit it outputs:

$clean: string= 123456, 654321, 852963
$exploded: array= Array
Array
(
[0] => 123456, 654321, 852963
)

As you will notice the output should return a 4 row array. If I set the output to the remmed out line and rem out the other line it outputs as expected.

What is wrong with said array