Look Up select box is not working via integration

var taskSysId = '5f1f516dc35203d05a76d5fe0501315d';
var grTask = new GlideRecord('sc_task');

if (grTask.get(taskSysId)) {
var ritmSysId = grTask.request_item.toString();
gs.info("Found Parent RITM: " + ritmSysId);

var test = new x_custom_scope.CustomScriptInclude();
var variableJSON = test.getVariableJSON(ritmSysId);

gs.info("Variable JSON Output:\n" + JSON.stringify(variableJSON, null, 4));
} else {
gs.error("Could not find an sc_task record with the provided sys_id: " + taskSysId);
}

...
var variableJSON = CustomScriptInclude.getVariableJSON(current.request_item.toString());
....

var payload = {};
...
payload.variables = variableJSON;
....

// Genericized custom table name
var transactionlogGr = new GlideRecord('x_custom_scope_transaction_log');
transactionlogGr.initialize();

transactionlogGr.payload = JSON.stringify(payload);

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