To be clear, there are three capture scenes in the storage shed, not the warehouse (that's the bigger space you go to first.) Getting all three will change battle gameplay as well. As for the others, I'll give you some time to poke around before giving it away: scene hunting is a lot of the fun of these games, and with one exception most of what's in this one should be pretty easy to find.
Yes, you're right, in the storage shed, not in the warehouse. But I don't think it's all that obvious. For example, on this branch of the plot, I came out by accident. I forgot to look at the pier and immediately went to the guards of the stairs, where I lost and noticed that I didn’t take the flash dodge. Normally, there is no other boars alive when I come to the stairs. So, I will try to search, I hope I will lucky :)