Tonight I was out at a local rest./bar and was faced with a dilemma. I'm relatively new to this PUA stuff, so I really didn't know how to handle this. Basically, my friends and I are talking and having some drinks at our table. I notice this buss girl (HB

standing around waiting for a table to clear off so she can do her job. This random guy who had been a customer then comes up to her and starts talking to her. She's clearly disinterested based on her body language. She makes several efforts to get away from him, incl. going to sit at a table by herself, but he keeps following her. He keeps talking and she's sitting there w/ her head in her hand showing little to no emotion.
I wanted so badly to rescue this girl and take my shot but didn't know how. It seemed like an ethical dilemma in terms of guy code to try and swoop her away from him, even if it was clear he was failing. I also wanted to avoid confrontation with him. I ended up leaving with my friends before I could say anything.
Should this situation come up again, how do I handle it? Should I go over and say something to try and get him to go away (if so, how do I handle it if he causes a scene?)?
Should I maybe try to summon her away from him (as if I needed something professional) and then say something like, "Sorry dont need anything but u looked bored so I had to rescue you."? I wrestled with this one for awhile, ultimately deciding not to b/c it seemed kind of weird and out of my element/
Or does guy code permit I let him do whatever it is he's doing and just have to wait my turn?
I was very disappointed that I did nothing but I was very confused, so any help is appreciated.