I have my doubts. Passive is just that. The current cameras do not project any sort of beam so there's nothing to be seen. They have a sensor inside that can detect rapid changes in the amount of heat / light they receive across a very small portion of their surface. The only time anything ever projects from them is the flash. Stands to reason that if a BF saw the flash from the camera when a deer tripped it, then the BF might avoid the location of the camera, but the camera itself might as well be a lump of coal. If there's anything, it's the charge on the battery or the smell of the plastic. I doubt those, too, because 50% of cameras not place with thought to air movement are downwind of their target, undetectable by smell, and hopefully all of those placed with thought to air movement are out of the air current where they can be smelled. High pitched buzz / whine .. maybe, but that has been tested with some mighty sensitive detection equipment without any proof of detection.
I tried an experiment a couple years ago. I set up a camera w/o batteries in the field of view of another camera, then tripped that camera at night to see what the camo plastic case looks like under I.R. It was a rectangular gray/black box, no sign of any camo. So supposing BF really can see in the infared end of the spectrum .. I would think that trail cams we place and thing are invisible would be rectangular boxes, plain as day, strapped to the tree, to them.
Another thing .. observation. Though sometimes critters appear to see the cameras, I'm not convinced. I have thousands of pictures of deer, elk, bear, coyotes, skunks, etc which appear completely oblivious to the camera that is taking their picture.
My cameras have a dark red cover over the IR flash and another over the lens. The one over the lens especially will glow blood red if it is hit by strong light from the side. That could be a piece of the detection puzzle.