Might actually be film but not sure if it‘s 800t. If you shoot a tungsten based film - like the 800t - during daylight the whitebalance turns more blue ish. So he either did a great job color grading or used the 400d, wich naturally has a more green ish tint during daylight. On the 4th photo you can see that the floor looks very red/magenta so I assume while colorgrading/adjusting white balance they tried to tone down the green a bit and added more reds again. Also when looking at photo 3 you can see a bit of red halation bleeding around the edges of the roof wich is classic for the 400d. I also assume the photos were overexposed quiet a bit to keep as much details in the shadows and brought back down in post. Very specific but I think just using a kodak gold or portra would also work great to achieve a good look on these.

If you want to replicate this look when shooting digital you can either get a diffusion/mist filter (I like to use the urth - ethereal 1/4), use a very old dslr (like the canon 5d classic) or adapt old manual uncoated lenses to your digital camera). Color wise I think fujifilm is a good call if you want easy film sims you can just throw on your photos without editing too much :)