Weird bug in Defend Carrier level

[Badhabit]

Run in to a bug in this that I dont remember I run in to when original came out.
--At save Carrier's reactor mission. After NPC say what player need to do(the room where marines try to defend 2 doors). player had to go shutdown a switch, and walk pass the chest deep water where the door area will give out shock, then player need to jump up to a room where both side has glass windows and then need climb up ladder, and need to go in to a crawlspace, BUT I cant get pass that door of the cralspace!!!! Crawl or prone dont help, its as if there is invisible wall blocking that door.
Any tip or help how to pass this bug?

In this youtube Crysis walktrough You can see the area I am talking about. Clearly this player didnt run in to this bug.
time of it is 3:09:47
https://www.youtube.com/watch?v=TNZWeH9PxAE&t=11390s

[rkarp]

I have had this, too. Maybe once or twice over a two year span so very infrequently. I either kept at it until I got through or else quite the game and restarted it. Whichever, eventually I got through it.

[Polychrome]

I ended up figuring out that if you spam Prone while trying to get in you will 99% of the times get through the awful collision barrier.