In the quest step before the one you're on, there should be a choice between trying to save karen and becoming a slut. If you chose becoming a slut, the main quest stops there. Do you know if you made that choice?
Oh, now I understand. And I almost sure I chose to save her back then.
Yes, I thought there is no possibility to go further if you chose to became a slut, and as I say I've already complete almost everything through the main quest. I saved Karen, reached the caves of resistance, we ran away through barbarian tunnels and end up in a mansion (new base), and we saw the big evil tower north to the town, which can brainwash everybody... And after that we returned to the base, and my characters refuse to go to the town again. But now I have "A night to remember" quest, which says I must go to the bar, but I can't. And it prevents me from the latest main quest updates.
Also I already saved Amy the slime girl.
360 days ago(+1)
So, if this still relevant for you: when you reach the door to Amy's lab, just go further to the left. You'll pass "test room 2" and "test room 1", then go down through the door with yellow indicator - it should be open. This is dr. Weber's office, just take her keycard from the table in front of you and go back to the lab.