Hey there! I'm playing the "Flooded District" mission on XBox, and I've run into a potentially game-ending glitch. I hope I'm mistaken!

After dropping down into the Old Dunwall Sewer via the weeper-ridden door place, I follow the indication marker to the gate, which is locked, prompting a new objective: to find the master sewer key. I get a new objective marker for the key. Then, I go talk to the thug, get the whole Slackjaw/rats speech, but then there's a problem.

The grate near the red pipe is closed, as if I didn't do the Granny/Slackjaw sidequests (which I did). I have watched NUMEROUS walkthroughs on YouTube that show every person walking into that sewer area with an opening above the red pipe. That opening does not exist for me, it's covered by a grate. I've restarted from the beginning of the weeper area to no avail. I'm trapped. The gate is locked, the grate is closed.

I've also googled it and no one seems to be having this problem...

Did I miss something?

What's happening!?

Please help...I don't want to lose all my work