A highly fortunate coincidence

I don't have the details of what I'm going to talk about memorized precisely or anything, so vagueness may abound.

  In the middle of winter a few years ago, my family (dad, mom, and my four brothers and sisters) went "up north" and stayed in a hotel near Otter Tail, MN to go snowmobiling. One of the afternoons while we were there, my mom and dad went out on the trails. Along the way, dad lost control of his snowmobile, and ended up jumping over a snowdrift, landing and getting hurt pretty badly.
  When they went to the hospital, a CT scan was ordered, and from this scan doctors noticed a suspicious growth in his abdomen. Initially we all feared it was cancer - tests later revealed it was not cancer but Castleman's disease. A few months later (after finding one of the best doctors for the disease) my dad had surgery to remove the tumor (which was difficult because it had grown on his intestine, and had some tricky blood vessels growing) and now he's recovered and will be fine.
  Naturally, most of my family (and dad himself) attribute the discovery of the tumor to God - drawing especially from the fact that the CT scan responsible for finding it was ordered seemingly on a whim. My family (who are Lutherans) see the snowmobile accident as a higher power intervening in my dad's life, and getting him into the hospital and having a scan done to find the growth. If it hadn't been found, the growth would have metastasized and spread, and, well, that wouldn't have been very good.
  On the other hand, I am an atheist. Don't get me wrong, I am very grateful the disease was spotted and my dad got the treatment he needed. I just think the accident was a very fortunate (in the long run) coincidence.
  I'll take a step back here. I don't want this to become a diatribe against believing in a higher power being behind fortunate events. I respect my family's beliefs on that matter. Even so, the way I see it is that dad's snowmobile accident didn't change the fact that he had Castleman's disease: it just led his doctors to finding the growth that led them to detecting the disease. As for why the CT scan was performed, I feel it was to look for any internal injuries they may have otherwise overlooked. Granted, I'm not a doctor, that's just my opinion. Besides, given the symptoms of Castleman's disease (high fevers, anemia, weight loss, loss of appetite, and low white blood cell counts -- Wikipedia) my dad's case would most likely have been detected at some point; whether that would have happened before it spread and became multicentric, we can't really know, can we? I completely understand why my dad and others in my family, being of religious tendencies, are apt to attribute his accident to some higher power - it was unlikely that my dad would crash the snowmobile, after which it was fortunate that a scan was done where doctors managed to find the growth in his abdomen. Just because it's unlikely and very fortunate, doesn't necessarily mean a higher power was looking after my dad. But I'll say again, I'm okay with my family's beliefs on the matter; I just don't share in those beliefs.


(In case this was confusing: the subject position I considered is religious belief; the specific claim I addressed is whether some higher power led to the discovery of my dad's tumors; and I aimed to explain how I see it as just a very lucky accident, not as something brought about by a higher power.)