OK, put the site in "Debug Mode"... then go through the process and get the bad quote... then manually update the url to go to /checkout_failure.php.
View source on that page and it will give you the full communication with UPS and we can see if the correct values are in there or not.
When you view source, copy all of the text and update the private message area with all of the code you see there and I can see if I can give advice on how to correct the problem.