Definitely something I'd try to handle verbally. Your supervisors likely had a reason for why they selected you, reasons they may likely not be willing to divulge. Could be anything from thinking you'll sort things out, to someone banging someone's girlfriend or you were just the unlucky one the Sgt picked. Your unit needs the position filled, and unless you have a solid reason as to why you shouldn't be there your CO will not undermine your CoC's choice of you simply cause you're not happy. Support sections are regularly manned by people who are working beyond the scope of their trade, this is what you signed up for.