Easier than I thought. We need the AppEvents interface. You should be able to adapt this code to your needs:

use warnings;
use strict;

use Win32::OLE qw(EVENTS);
my $Excel = Win32::OLE->new('Excel.Application');
$Excel->{Visible} = 1;
my $Workbook = $Excel->Workbooks->Add;


sub Event {
            my ($Obj,$Event,@Args) = @_;
            print "Event triggered: '$Event'\n";
        }

Win32::OLE->WithEvents($Excel, \&Event, 'AppEvents');

while (1) {
    sleep(1);
    Win32::OLE->SpinMessageLoop;
}
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--
May the Source be with you.

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