Is $200 to move HVAC ducting and add new vent opening a fair price?

I am playing around with a new bathroom plumbing layout and I think I could get the layout I want if I move some HVAC ducting around to make space for plumbing. I would still need a vent in this room, so I need some options. I know this would mean pulling pipes through floor joists, and I got a structural engineer to look at it and confirm that I can do this if I use some joist reinforcement kits. I am wondering if I can just make another opening in the vertical ducting in this room, as there's another opening on the other side of that ducting, which would result in two vent openings right next to each other, like a "T". I am concerned if that would cause air flow issues. Another idea I had was to maybe pull some more ducting through a non-load bearing stud, but that seems like a lot of work. I've received three quotes so far and am trying to figure out the best option.