The witness accounts I read stated he was seated, got up and left through that door but propped it open (so as to be able to get back in) and then returned. I tend to believe that as you would notice someone propping a door open since one tends to notice anomalies.
All you need is a small wedge of wood to keep the latch from engaging.
We have all been in situations to witness anomalies. We have been programed to say nothing, but we do file them away in our minds.
These days any anomaly needs to be questioned.
I read yesterday during the “breaking” time frame that Jansing and her crew @ PMSNBC were already surmising on air that he used the same “Watergate” technique of taping over the auto-locking bolt. Yup, they actually referred to Watergate. Let no good crisis....