I'm pretty sure Saul was on Vancomycin, which is a different class of antibiotic. I didn't go back and relisten though, so could be wrong. The hospital would certainly have both a tetracycline agent and Vanc on hand, along with other antibiotics.
Also, further thinking...I think fluoride may cause yellowing of bones in high exposures. And it certainly hardens them. Could have been in the haze as a gas!