Eh, you messed up. Own up to it and be more careful next time.
It is true that I didn't see that information near the text field in the iFrame. However, the hit itself was some sort of software that the requester apparently was developing and while using said software, the requester never ever mentioned that I needed to know the mean wage of Market Research Analysts in the iFrame's instructions or in the survey software itself. Additionally, the survey software did not show me anything related to Market Research Analysts (not trying to give away survey content but it was showing me information about computer analysts) or if it was there, it definitely was not apparent.
So you are correct that I should have paid better attention to that text field. However, as I said, I would not have known anything about researching data on Market Research Analysts anyway because the hit title nor the requester mentioned anything about it except near that text field.
Basically, the requester has no TO so I assume that the person is new to mTurk. It's no big deal but it is slightly annoying that they would ask for that type of information instead of providing a traditional survey code.