Exceptions don't work after the script processing has run

Content

How do I make exceptions work when I have a custom script processing the rows? Should it still work because I can't make it work

So let's say I have a column that outputs 0. I then have a custom script that changes this to 1. If I have an exception highlight where the row is 1, it doesn't work

Any ideas?

I have added the code to this question. The resulting value might be blank and if so, I want to highlight the row accordingly. Please advise

Code Snippet

$a = rtrim(trim(str_replace('invalid@email.com','',$rows[0][4]->val)),",");


$b = explode(",",$a);
$c = array_map('trim', $b);
$d = array_filter($c);
$e = array_unique($d);
$f = implode ($e, ",");

if ($f=='' || empty($f)) {
$rows[0][5]->val = 0;
}

$rows[0][4]->val = $f;