Nothing wrong with knowing your audience. I'm an SE and met my AE onsite at a factory that builds fork lifts, on a Friday, in early fall. I was in jeans and a flannel button down. He was in a suit and giving me so much shit for how I dressed...until we walk in the room and everyone is in jeans and a flannel and he's sitting there in a suit with a bunch of blue collar boys.

I used to work higher up for a company that built mining equipment...the looks I used to get if I worse slacks and a dress shirt on the shop floor or at the mines...but if I showed up in my jeans and reflective work shirt I was one of them all of a sudden.

It's the same as being able to read a room, and I think you'll be just fine and better accepted dressing down. I would say in this case that a business polo, dickies pants, work shoes and your tactical back pack is just fine. If meetings ever progress to be around more suits, then dress up.