Sorry about my wrong word choice there. In the craft of story there are no absolutes. What I meant was it naturally shouldn't, given more details from that movie. Conflict can come from anywhere really. I like how you thought outside the confines of the "expected" throughline progression. Usually I find one kinda needs to fish for it. One thing I've found, depending on the work, is that some throughlines are obvious and some aren't quite so easy to see. There's an old saying from med school : "Seek what you look for, and look for what you recognize". Seek a Domain that strikes you. Either OS, MC, IC or RS. I then trust the software to pick the dynamic pair. I later cross check that to see if the argument holds true. If it indeed makes sense, then I know I've got a hot trail. If it doesn't, then I reexamine what I thought instead till it feels right. One thing that helped me was watching a lot of the breakdown videos. So I'll do my own analysis, then compare with the official ones to see where I might have been off. I'm usually right about the domains. It's the issues, and so o I tend to miss more. If you watch the video analysis,you'll notice Chris has a habit of going over the static plot points before even going to the throughlines. He'll ask, " is the MC a do-er? Is this a Decision or action driven narrative?" etc
There's another post Jim made on Dramatic tension as well. So I kind of use that too. Usually the dramatic tension in most first acts comes from the Pre-requisites. And the second acts, from the Requirements. This helps me narrow down my throughlines. Just like the craft of writing, there is no one way. One of the most optimum examples that greatly helped is the story forming video of The Babadook. You should see that movie. Chris breaks it down so well that you'll glean a lot of storyforming tricks there.