PHPSpreadsheet Convert Cell Formula to plain text

I'm using PHPSpreadSheet to read some cells in a range and saving it to a CSV. Everything is great except when my script encounters a formula it renders the cells formula like so in the CSV:

=CONCAT(B27," RNA QC")

instead of:

ONDr641 RNA QC

There are only a few rows where there are formulas. Everything else is text.

I have read that the 3rd argument in the rangeToArray function allows formulas be calculated (the equivalent of getCalculatedValue() for each cell). If I set that to true it stills renders it wrong. I've tried setting the explicit value and that did not work either.

How can I fix this? Any advice - I would most appreciate it!!

while ($data_detected) {
        $start_cell = "B" .
        strval(($start_row + ($chunk_size * ($pass - 1))));
        $end_cell = "AA" .
        strval(($start_row - 1) + ($chunk_size * $pass));
        
        $cell_range = $start_cell . ":" . $end_cell;


        $sheet_data = $spreadsheet->getActiveSheet()->rangeToArray(
                        $cell_range, null, false, false, true);

        $chunk_has_data = False;

        foreach ($sheet_data as $row_number => $row) {
            // Filter out rows that are entirely blank. If even a single
            // element in a row has data, then the row will be included...
            if (array_filter($row)) {
                // Set a flag that we have detected data in this pass.
                $chunk_has_data = true;

                foreach ($headers as $column_letter => $column_name) {
                    $row[$column_name] = $row[$column_letter];

                    unset($row[$column_letter]);
                }

                // Save the row number so that we can refer to it later.
                $row['row_number'] = $row_number;
                array_push($rows_with_data, $row);

            } else {
                // Row was empty
                $chunk_has_data = False;
            }
        }

source https://stackoverflow.com/questions/77083951/phpspreadsheet-convert-cell-formula-to-plain-text