I guess skepticism has its own rewards.
Fuel pump replacement is very expensive; it’s worth paying for a second opinion. Or he could just replace the fuel pump, as requested, and make some $$$, then make more $$$ when she returns because the noise is still there.
Back in the late 90s, before the Commercial Internet was going full-blast, I bought a new car. When talking with the salesman, I used their “codes”, that I had searched for and found, in my conversation as to what I thought the cost should be. He looked at me in shock and said “You know our codes?”
I don’t blame anyone for looking up any issue online to know something about it before going to get it checked out. Women especially are ripped off and lied to on a regular basis so if a mechanic is snarky about you saying you looked it up leave and find someone who will listen and discuss the issue. I wouldn’t go in with an attitude but I would not trust a salesman, mechanic, doctor or a recruiter! :-p