I'd try saving, closing out the game completely, then re-opening the game. Then try to go to bed during the night (I go for close to midnight but that might not be necessary).
The end of the quest only triggers by event with the MC getting awoken from their sleep, and if you don't trigger it promptly enough it seems to muddle something in the background.
It should all be good so long as the quest prompt still shows you as being >2/2 girls after you reboot and open your save again (amusingly, it keeps count way past that and can read as 9/2 girls and so forth. Makes me wonder how long the game will keep count...)