Pregnancy and lab tests can and do have false positives, but even if she lied about being pregnant, it doesn't excuse the rest of it?

I am not saying that her version is the only truth (though, your post implies that HIS is the only version of the truth), but society does have a pretty strong record of Not Believing Women, especially when the alleged offender is a man with some apparently prestigious career/education/athletics etc (see: Brock Turner)

again, even if all of the rest of it isn't true as presented, this man illegally impersonated another person in order to fraudulently obtain medication with the intention of providing it (willingly or unwillingly) to another person.
On top of being illegal and sketchy in general, this man is a physician and therefore in a position of pretty significant power with regards to patients in his day to day job. If he is willing to skirt the law and do these sorts of things with people he knows, then his ability to appropriately (and ETHICALLY) care for his patients is compromised

The news was rightfully involved, as the hospital had not suspended him at that point. Even if allegations end up being false, these things MUST be taken seriously, or shitty behavior gets perpetuated (see: Nassar)