I would say there's very little to no chance of making a fire with natural materials. I don't remember how Tom Hanks did it in castaway, but this would entail a bow drill or hand drill or other methods which are even more difficult. Using a bow drill made from scratch would take hours even for survival experts, and even that requres shoelaces or some other cordage, I doubt it could be done with natural cordage unless you're an expert in making natural cordage.

As I've said, the army kit is likely to have some tools for igniting a fire, unlike everything else on that list(most radio batteries don't have enough voltage to create a spark, and who knows if the lense from the sextant is powerful enough, or if it can easily be seperated).
It is primarily for this reason I support it's place on the list, and that it may contain fishing gear or other useful supplies. However, I would consider putting the water and the plastic sheet above it, with the army supplies as #4, since water is certainly more important than fire.