Why was Geneva Hine trying to get into any of the office doors along the hallway?
Answer: She wanted to get to a South side window ASAP to see what was going on outside in Dealey Plaza.
Failing in her efforts at both doors she knocked on, it is a reasonable probability that Geneva Hine then went to the next best alternative South side window: in the Womens bathroom at the corner side of the TSBD, where she would have had a perspective to have seen the Newmans on the GK and other persons, who were laying on the ground.
Its doubtful she could have seen those people from the West side window of that 2nd floor office.
If my hypothetical is correct, then Geneva Hine might have been in the Womens bathroom as early as 45 seconds post shots, and stayed there for up to 2 more minutes. If so, she would have missed Oswald exiting the 2nd floor office at either 2 min 30 sec or at 60 sec, depending on if Mrs Reid got up to the 2nd floor office as early as 50 sec post shots, which is possible, although currently not probable, unless the Couch film location of Mrs Reid as the "white scarf heavy set woman" is not Mrs Reid.
