I can't speak for Tiger Woods, or even professional golf, but I can tell you that I trained at a gym with athletes from another sport.
Everyone who was a professional was on PEDs. It was an open secret.
As far as him not bulking up or having injuries... not all PEDs do the same. In fact, depending on what injuries he had, it might point to the positive use of PEDs. (For instance, it's amazing how many athletes tear their ACL compared to the general population - it's a very strong ligament usually. Certain PEDs upset the natural muscle strength to ligament strength though, hence pro wrestlers and football players mysteriously have weak ACLS.)
Or, ever wondered how Olympians seem to be diabetic at a higher rate than the normal populace? (Insulin grows muscle.)
I'm not saying one way or another, but professional athletes should be viewed with extreme scepticism.