It looks like it is having issues since your unique key isn't defined as a number column and has a lot of preceding zeros. It should fix it if you update line 348 and replace this:
document.getElementById('WADADeleteRecordID').value=<?php echo($row_WADAenzosevents['CMSID']); ?>;
with this:
document.getElementById('WADADeleteRecordID').value='<?php echo($row_WADAenzosevents['CMSID']); ?>';