Mostly agree, though it's worth noting that the multiplier can also be greater than one if money gets shifted to an industry that creates more jobs per dollar than the malaria nets.

Want to add this to #1:

a) Death & sickness are bad for the economy. It's pretty uncontested that more people use malaria nets than when they are provided for free (can link research on this if necessary). When someone is sick, it's time that they can't spend in the labor force. When someone gets sick a lot as a child, it affects them so that they are a less productive worker in the future. When your child is sick, you have to spend time taking care of them that could have otherwise been hours you earned a wage, spent on goods, etc. So in that regard, this is probably an outweighing factor to a couple jobs.

b) Even if malaria nets don't effect wages and productivity at all, the money that would have gone to the malaria net maker doesn't just disappear, it's simply spent somewhere else. So jobs don't go away, they are just created in other areas.

So it's not just weighing job creation vs. malaria prevention, it's that malaria prevention probably helps job creation.