I would also like to confirm that this is still an issue that should be looked at by the developers. I fixed it on the third try but i can’t be to specific about what i did because i forgot. But the gist is that i never knew Gixx was at the entrance and just folowed my marker to Siera, and enter her cut scene.
In short my glitch was a result of a weird bypass, and could be fixed by restarting and forcing the events to happen the way they were suppose to (ignoring the marker).