Error while executing query: Element 'email' unknown.

Good afternoon, everyone. I'm currently working on uploading an encrypted email file into Adobe Campaign using the Read List activity. 

Subsequent to this step, I have a JavaScript activity in which I've implemented the following code:

function decryptValue(encryptedValue) {
var decryptedValue = '';
for (var i = 0; i < encryptedValue.length; i++) {
var encryptedCharCode = encryptedValue.charCodeAt(i);
var decryptedCharCode = encryptedCharCode - 1;
decryptedValue += String.fromCharCode(decryptedCharCode);
}
return decryptedValue;
}

var query = xtk.queryDef.create(
'<queryDef schema="temp:readGroup" operation="select">' +
'<select>' +
'<node expr="email"/>' +
'</select>' +
'</queryDef>'
);
var records = query.ExecuteQuery();

for (var i = 0; i < records.length; i++) {
var decryptedEmail = decryptValue(records[i].email);

instance.vars.email = decryptedEmail;

logInfo("Decrypted Email is: " + instance.vars.email);
}

After this code, I will need to update that list with an List Update activity, but I am getting this message error while executing the JavaScript activity:

And my workflow loos like this: