Transitioning to his own room

I need advice on how to get my 16 month old to sleep in his own room. I'm planning on buying a room camera and all of that but it's like he *senses* when I leave. Both of our rooms are upstairs. Should I leave his door open so he can come into our room in the morning? He goes up and down the stairs perfect. Has never fallen but I feel like it's too big of a risk to leave his door open. Gates dont work because he just smashes them down. Is it okay to close his door? I tried to do everything "perfectly" and by the book but the one area I didnt was sleeping. We cosleep with his mattress on the floor. I had extremely bad post partum ptsd from NICU and I was scared of him possibly dying if he wasnt watched by me all of the time. I really want him to be up and okay with sleeping in his own room before we have a second. Any advice? Please and thank you in advanced 💙

*please DO NOT suggest the cry it out method. My son has an airway defect. Crying it out can cause him to go into respiratory distress.