Evil Inside

You can find the camera on round 11 inside of the wardrobe in the bedroom after interacting with the picture on the wall by the end of the hallway.
I show this Achievement in my Walkthrough at 19:05 minutes into the video.
Quick Achievement Walkthrough + Commentary & timestamps below.
0:20 Round 1
1:19 Round 2
3:00 Round 3
3:05 Master of unlocking
4:29 Round 4
5:05 Secrets in the dark
6:49 Round 5
7:49 LightAtTheEndOfTheTunnel
8:39 Round 6
8:55 The Observer
10:14 Memories
10:57 Round 7
11:16 Be ready for the BBQ
11:56 God ends here
13:02 Round 8
13:05 Music for my ears
14:22 Round 9
17:04 Round 10
17:19 Back to life
18:38 Round 11
18:45 Perfectionist
19:05 Smile
19:36 Discover the truth
20:10 See the name of Gods