That timeline seems to ignore the German WWII work entirely - the He-219 'Uhu' had ejector seats, flew in 1941, was operational in 1943, and last time I checked was the first operational a/c type to have them.
Edit - a quick search brings the following:
The first ever successful escape by ejection seat (true, not a combat mission) was made by the Argus test pilot Schenk who ejected from the He280V1 on 13th Jan 1943 during a pulse engine test.
The first combat ejection took place on the night of 19th May 43' when Lt Otto Fries (pilot), Hptm von Bonin (radar operator) and Fw Staffa (observer/gunner) of II./NJG.1 ejected out of their burning He219 'Uhu' over the Florennes area. They were believed to have been shot down by Wg Cmdr Norman J.Starr of 605Sqn while flying a Mosquito VI on an intruder mission. The Heinkel He219 was the world's first production aircraft fitted with ejection seats.
Edit - a bit more digging and it looks like the He-280 was the first aircraft to have an ejector seat; the Do-335 also had one. Seems to be a lot of stuff on the net that assumes Martin Baker invented the thing first and nothing happened before 1946!!