This isn't my area of expertise, but a quick review suggests that they are basing the numbers on a single study, which wasn't an RCT - it was a 'before and after' with an attempt at a control group.
That doesn't mean it isn't worth looking into, for sure, but I could equally believe that the extra rigour of an RCT could move the cost per lives saved from ~$1200 to a number several times higher than that.
It still merits furthers investigation though.
I'm not an expert but skimmed the two documents that seemed most relevant. The mortality rate analysis of the study and how they derive the $1235 per life estimate from it.
Two things that I noticed, which jlewars didn't mention yet:
[Again not an expert, so don't make any conclusions based on what I write here.]
So, even if Noora Health's intervention was as effective as they suggest, the question of how well the intervention is scaled for mothers in other contexts is a separate question. (However, if they use additional funding in a similar context this is not such a big problem.)