How do i get through the vents? I saw a comment mention I had to move forward 10 times, but I have done far more already.
I do find a room eventually, but my only options is to shoot which alerts the enemies, or to use a blade which sends me back to the vents.
That room you are talking about is just a random event you can encounter in the second part of the vents.
I can't remember what the conditions are to trigger the ending in the second vents section, but there is probably some event, quest, or scene you haven't encountered yet in the game.
Check out your status in the Medbay and see if there are any quests that are active.
Sometimes the game needs time to advance before triggering some events or scenes and sleeping in the lab in the vents doesn't seem to trigger them. Try sleeping in the Medbay and speaking to all of the NPC's a few times, there might be something you need to discuss or a scene you need to trigger to advance through the vents and get to the ending.