It doesn't matter what the flight attendant's problem was.
She appears to have treated this woman - whether because of race, gender, age or some other factor - suspiciously and condescendingly, and then was simultaneously more trusting of another passenger, despite not yet having seen his credentials. Heck, for all we know maybe her issue was that she didn't know an ob gyn is an actual doctor!
None of that changes the fact that, ultimately, the attendant felt the need to apologize to Dr. Tamika Cross, use her expertise (I suppose the older gentleman wasn't as helpful - or possibly not as much of a doctor - as she'd hoped?) and try to offer her compensation (possibly in the hope she wouldn't take this any further).
Unless a radically different version of the story comes out, I think Dr. Tamika Cross is owed an apology and compensation, regardless of why all this went down.
And, all things considered, I could hardly criticize her if she did believe it was a matter of race, whether it is or isn't. When racial issues smack you in the face every day, you can hardly be blamed for seeing every new incident in that light. But, even in light of that, she was still fair-minded enough to indicate it could also have been her gender or her age that caused her to be judged unfairly.