Password 2: QR code
If you pick up an item and then die in the first level by going to the far left, a bunch of imagery will flash, one of these images have a QR code, the QR code leads you to this video:
In this video, there is a text that appears for a few frames, it reads "Y2hvb3Nl"
that is the second password
P.S. In the second level there is a mirror at the end of the hall, if you interact with it, you get an undertale reference! ("despite everything, its still you" is a text that pops up if you look in the mirror in new home/asgores kingdom)