If I am testing the antimicrobial activity of a bacteria in a specific agar (like Nutrient Agar), shouldn't I use the same media for other tests such as biochemical analysis?

I am a bit lost as to why my superior would choose another agar (ISP 2-7 agar). Although that agar is specific for that microorganism, shouldn't I check the biochemical activity also present during the antimicrobial activity assay done in NA?

EDIT: I am using Mueller Hinton Agar. I just wrote NA since that was the initial agar they chose during the proposal.