I just gave it a quick look, the issue lays in the mechanics of the eject mechanism.
As you can see from the picture, there’s a rotating cam, which acts on a pin, translating rotational movement into linear one.
Apparently, nothing looks damaged, just kind of snapped out of position (even though there seems to be a tiny gear train that I still have to inspect, but the cam always rotates back to initial position, so it should be OK).
As is now, as the cam reaches rearmost position (270 deg), the pin just slips under the cam and the sledge is abruptly pulled back to closed position by the action of the springs.
Seems to me that by fiddling with the mechanical eject and pushing the eject button at the same time, the whole mechanism went out of synchronization.
I’d need to see a working drive for figuring out a fix…