She has never had a cleaning, she is a rescue, and she had blood work a year ago when I had the mammary tumor checked. She eats and drinks normally. That is the only gland that is swollen. Her odor smells like feces.
Bad breath can signal a problem elsewhere in the body...everything from ongoing stomach issues to liver or kidney disease to even dental disease. Because there are so many possibilities, I think the absolute best thing to do is to have your dog looked at by her regular vet.
At the vet, they'll check her mouth thoroughly for any foreign body that could be trapped there (I once saw a dog with horrible breath..during the examination, they found a piece of bone she'd been chewing on stuck between her teeth and rotting...once they removed it, her breath really improved!) and possibly run a little bloodwork to make sure that all her values are within the normal range (meaning all her organs are functioning the way they're supposed to).
Because of her age/breed, I strongly suspect that the bad breath is due to her poor dental health. Dogs who have never had a dental cleaning often have incredibly bad breath, that can smell like feces and even like garbage. You may want to talk to your vet about a dental cleaning. Once her teeth are cleaned, her breath will improve a million percent!!
I hope this helps!!