nlapiLoadRecord on Vendors

The nlapiLoadRecord and nlapiSearchRecord functions in the SuiteScript 1.0 API are not working correctly for Vendor records. NOTE: This instance is a Sandbox environment.

var vendor_record = nlapiLoadRecord('vendor', 1416); // 1416 is a valid record and DOES exist

vend_filters[0] = new nlobjSearchFilter('internalid', null, 'anyof', 1416); // 1416 is a valid record and DOES exist
                
var vend_searchresults = nlapiSearchRecord('vendor', null, vend_filters, null);

Both of these API functions return an extremely vague error message page that simply reads 'id'.

When I go to my Script Execution Log, the error message title reads: 'SSS_MISSING_REQD_ARGUMENT' and the message is 'id'.

This leads me to believe that the system thinks that I have no provided an ID at all (if it was an invalid ID, the message would read 'record does not exist').