Why would you overcomplicate this? Use Spreadsheet::Read (or Spreadsheet::ParseXLSX directly) to read your Excel sheet and then use Text::CSV_XS (or Text::CSV) on the content of the cell(s) you want to split

Here is a tested example. The pm1226189.xlsx that I used has comma-separated fields that also include newlines and quotation. If your Excel also contains encoded fields, you probably have to deal with that inside the inner loop

#!/pro/bin/perl

use 5.14.1;
use warnings;

use Data::Peek;
use Spreadsheet::Read;
use Text::CSV_XS;

my $book  = Spreadsheet::Read->new ("pm1226189.xlsx") or
    die "Cannot read spreadsheet: $!\n";
my $sheet = $book->sheet (1) or die "Book has no sheets\n";

my $csv = Text::CSV_XS->new ({
    binary           => 1,
    auto_diag        => 1,
    allow_whitespace => 1,
    });

my @data;
foreach my $col (1 .. $sheet->maxcol) {
    foreach my $row (1 .. $sheet->maxrow) {
        my $cell = $sheet->cell ($col, $row);
        if ($cell && $cell =~ m/,/) {
            open my $fh, "<", \$cell;
            $data[$col][$row] = $csv->getline ($fh);
            close $fh;
            }
        else {
            $data[$col][$row] = $cell;
            }
        }
    }
DDumper \@data;
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